diff --git a/tests/baselines/reference/arrayCast.errors.txt b/tests/baselines/reference/arrayCast.errors.txt
index 3aebf139825..84ba7fd8b3f 100644
--- a/tests/baselines/reference/arrayCast.errors.txt
+++ b/tests/baselines/reference/arrayCast.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/arrayCast.ts(3,1): error TS2352: Neither type '{ foo: string; }[]' nor type '{ id: number; }[]' is assignable to the other.
   Type '{ foo: string; }' is not assignable to type '{ id: number; }'.
-    Property 'foo' does not exist on type '{ id: number; }'.
+    Object literal may only specify known properties and 'foo' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/arrayCast.ts (1 errors) ====
@@ -10,7 +10,7 @@ tests/cases/compiler/arrayCast.ts(3,1): error TS2352: Neither type '{ foo: strin
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2352: Neither type '{ foo: string; }[]' nor type '{ id: number; }[]' is assignable to the other.
 !!! error TS2352:   Type '{ foo: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2352:     Property 'foo' does not exist on type '{ id: number; }'.
+!!! error TS2352:     Object literal may only specify known properties and 'foo' does not exist in type '{ id: number; }'.
     
     // Should succeed, as the {} element causes the type of the array to be {}[]
     <{ id: number; }[]>[{ foo: "s" }, {}]; 
\ No newline at end of file
diff --git a/tests/baselines/reference/arrayLiteralTypeInference.errors.txt b/tests/baselines/reference/arrayLiteralTypeInference.errors.txt
index 4d381b77af9..65334ee9b95 100644
--- a/tests/baselines/reference/arrayLiteralTypeInference.errors.txt
+++ b/tests/baselines/reference/arrayLiteralTypeInference.errors.txt
@@ -1,11 +1,11 @@
 tests/cases/compiler/arrayLiteralTypeInference.ts(13,5): error TS2322: Type '({ id: number; trueness: boolean; } | { id: number; name: string; })[]' is not assignable to type 'Action[]'.
   Type '{ id: number; trueness: boolean; } | { id: number; name: string; }' is not assignable to type 'Action'.
     Type '{ id: number; trueness: boolean; }' is not assignable to type 'Action'.
-      Property 'trueness' does not exist on type 'Action'.
+      Object literal may only specify known properties and 'trueness' does not exist in type 'Action'.
 tests/cases/compiler/arrayLiteralTypeInference.ts(29,5): error TS2322: Type '({ id: number; trueness: boolean; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
   Type '{ id: number; trueness: boolean; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
     Type '{ id: number; trueness: boolean; }' is not assignable to type '{ id: number; }'.
-      Property 'trueness' does not exist on type '{ id: number; }'.
+      Object literal may only specify known properties and 'trueness' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/arrayLiteralTypeInference.ts (2 errors) ====
@@ -26,7 +26,7 @@ tests/cases/compiler/arrayLiteralTypeInference.ts(29,5): error TS2322: Type '({
 !!! error TS2322: Type '({ id: number; trueness: boolean; } | { id: number; name: string; })[]' is not assignable to type 'Action[]'.
 !!! error TS2322:   Type '{ id: number; trueness: boolean; } | { id: number; name: string; }' is not assignable to type 'Action'.
 !!! error TS2322:     Type '{ id: number; trueness: boolean; }' is not assignable to type 'Action'.
-!!! error TS2322:       Property 'trueness' does not exist on type 'Action'.
+!!! error TS2322:       Object literal may only specify known properties and 'trueness' does not exist in type 'Action'.
         { id: 2, trueness: false },
         { id: 3, name: "three" }
     ]
@@ -47,7 +47,7 @@ tests/cases/compiler/arrayLiteralTypeInference.ts(29,5): error TS2322: Type '({
 !!! error TS2322: Type '({ id: number; trueness: boolean; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
 !!! error TS2322:   Type '{ id: number; trueness: boolean; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
 !!! error TS2322:     Type '{ id: number; trueness: boolean; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:       Property 'trueness' does not exist on type '{ id: number; }'.
+!!! error TS2322:       Object literal may only specify known properties and 'trueness' does not exist in type '{ id: number; }'.
         [
             { id: 2, trueness: false },
             { id: 3, name: "three" }
diff --git a/tests/baselines/reference/arrayLiterals.errors.txt b/tests/baselines/reference/arrayLiterals.errors.txt
index 9bae14e36b3..fb0009e6a57 100644
--- a/tests/baselines/reference/arrayLiterals.errors.txt
+++ b/tests/baselines/reference/arrayLiterals.errors.txt
@@ -2,7 +2,7 @@ tests/cases/conformance/expressions/arrayLiterals/arrayLiterals.ts(24,5): error
   Index signatures are incompatible.
     Type '{ a: string; b: number; c: string; } | { a: string; b: number; c: number; }' is not assignable to type '{ a: string; b: number; }'.
       Type '{ a: string; b: number; c: string; }' is not assignable to type '{ a: string; b: number; }'.
-        Property 'c' does not exist on type '{ a: string; b: number; }'.
+        Object literal may only specify known properties and 'c' does not exist in type '{ a: string; b: number; }'.
 
 
 ==== tests/cases/conformance/expressions/arrayLiterals/arrayLiterals.ts (1 errors) ====
@@ -35,7 +35,7 @@ tests/cases/conformance/expressions/arrayLiterals/arrayLiterals.ts(24,5): error
 !!! error TS2322:   Index signatures are incompatible.
 !!! error TS2322:     Type '{ a: string; b: number; c: string; } | { a: string; b: number; c: number; }' is not assignable to type '{ a: string; b: number; }'.
 !!! error TS2322:       Type '{ a: string; b: number; c: string; }' is not assignable to type '{ a: string; b: number; }'.
-!!! error TS2322:         Property 'c' does not exist on type '{ a: string; b: number; }'.
+!!! error TS2322:         Object literal may only specify known properties and 'c' does not exist in type '{ a: string; b: number; }'.
     var context2 = [{ a: '', b: 0, c: '' }, { a: "", b: 3, c: 0 }];
     
     // Contextual type C with numeric index signature of type Base makes array literal of Derived have type Base[]
diff --git a/tests/baselines/reference/assignmentCompatBug2.errors.txt b/tests/baselines/reference/assignmentCompatBug2.errors.txt
index dcccaabca18..d12aad8a4bc 100644
--- a/tests/baselines/reference/assignmentCompatBug2.errors.txt
+++ b/tests/baselines/reference/assignmentCompatBug2.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/compiler/assignmentCompatBug2.ts(1,5): error TS2322: Type '{ a: number; }' is not assignable to type '{ b: number; }'.
-  Property 'a' does not exist on type '{ b: number; }'.
+  Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
 tests/cases/compiler/assignmentCompatBug2.ts(3,1): error TS2322: Type '{ a: number; }' is not assignable to type '{ b: number; }'.
-  Property 'a' does not exist on type '{ b: number; }'.
+  Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
 tests/cases/compiler/assignmentCompatBug2.ts(5,1): error TS2322: Type '{ b: number; a: number; }' is not assignable to type '{ b: number; }'.
-  Property 'a' does not exist on type '{ b: number; }'.
+  Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
 tests/cases/compiler/assignmentCompatBug2.ts(15,1): error TS2322: Type '{ f: (n: number) => number; g: (s: string) => number; }' is not assignable to type '{ f(n: number): number; g(s: string): number; m: number; n?: number; k?(a: any): any; }'.
   Property 'm' is missing in type '{ f: (n: number) => number; g: (s: string) => number; }'.
 tests/cases/compiler/assignmentCompatBug2.ts(20,1): error TS2322: Type '{ f: (n: number) => number; m: number; }' is not assignable to type '{ f(n: number): number; g(s: string): number; m: number; n?: number; k?(a: any): any; }'.
@@ -16,17 +16,17 @@ tests/cases/compiler/assignmentCompatBug2.ts(33,1): error TS2322: Type '{ f: (n:
     var b2: { b: number;} = { a: 0 }; // error
         ~~
 !!! error TS2322: Type '{ a: number; }' is not assignable to type '{ b: number; }'.
-!!! error TS2322:   Property 'a' does not exist on type '{ b: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
     
     b2 = { a: 0 }; // error
     ~~
 !!! error TS2322: Type '{ a: number; }' is not assignable to type '{ b: number; }'.
-!!! error TS2322:   Property 'a' does not exist on type '{ b: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
     
     b2 = {b: 0, a: 0 };
     ~~
 !!! error TS2322: Type '{ b: number; a: number; }' is not assignable to type '{ b: number; }'.
-!!! error TS2322:   Property 'a' does not exist on type '{ b: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'a' does not exist in type '{ b: number; }'.
     
     var b3: { f(n: number): number; g(s: string): number; m: number; n?: number; k?(a: any): any; };
     
diff --git a/tests/baselines/reference/assignmentCompatBug5.errors.txt b/tests/baselines/reference/assignmentCompatBug5.errors.txt
index 200829a8693..152f74d3c00 100644
--- a/tests/baselines/reference/assignmentCompatBug5.errors.txt
+++ b/tests/baselines/reference/assignmentCompatBug5.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/assignmentCompatBug5.ts(2,6): error TS2345: Argument of type '{ b: number; }' is not assignable to parameter of type '{ a: number; }'.
-  Property 'b' does not exist on type '{ a: number; }'.
+  Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
 tests/cases/compiler/assignmentCompatBug5.ts(5,6): error TS2345: Argument of type 'string[]' is not assignable to parameter of type 'number[]'.
   Type 'string' is not assignable to type 'number'.
 tests/cases/compiler/assignmentCompatBug5.ts(8,6): error TS2345: Argument of type '(s: string) => void' is not assignable to parameter of type '(n: number) => number'.
@@ -14,7 +14,7 @@ tests/cases/compiler/assignmentCompatBug5.ts(9,6): error TS2345: Argument of typ
     foo1({ b: 5 });
          ~~~~~~~~
 !!! error TS2345: Argument of type '{ b: number; }' is not assignable to parameter of type '{ a: number; }'.
-!!! error TS2345:   Property 'b' does not exist on type '{ a: number; }'.
+!!! error TS2345:   Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
     
     function foo2(x: number[]) { }
     foo2(["s", "t"]);
diff --git a/tests/baselines/reference/contextualTyping12.errors.txt b/tests/baselines/reference/contextualTyping12.errors.txt
index e1f05b432dc..3126ddbec50 100644
--- a/tests/baselines/reference/contextualTyping12.errors.txt
+++ b/tests/baselines/reference/contextualTyping12.errors.txt
@@ -1,7 +1,7 @@
 tests/cases/compiler/contextualTyping12.ts(1,13): error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-      Property 'name' does not exist on type '{ id: number; }'.
+      Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping12.ts (1 errors) ====
@@ -10,4 +10,4 @@ tests/cases/compiler/contextualTyping12.ts(1,13): error TS2322: Type '({ id: num
 !!! error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
 !!! error TS2322:   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
 !!! error TS2322:     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:       Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:       Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTyping17.errors.txt b/tests/baselines/reference/contextualTyping17.errors.txt
index e67d5958092..35cb4e03605 100644
--- a/tests/baselines/reference/contextualTyping17.errors.txt
+++ b/tests/baselines/reference/contextualTyping17.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/compiler/contextualTyping17.ts(1,33): error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-  Property 'name' does not exist on type '{ id: number; }'.
+  Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping17.ts (1 errors) ====
     var foo: {id:number;} = {id:4}; foo = {id: 5, name:"foo"};
                                     ~~~
 !!! error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:   Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTyping2.errors.txt b/tests/baselines/reference/contextualTyping2.errors.txt
index cc15a8bbbb1..9204e06a8b2 100644
--- a/tests/baselines/reference/contextualTyping2.errors.txt
+++ b/tests/baselines/reference/contextualTyping2.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/compiler/contextualTyping2.ts(1,5): error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-  Property 'name' does not exist on type '{ id: number; }'.
+  Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping2.ts (1 errors) ====
     var foo: {id:number;} = {id:4, name:"foo"};
         ~~~
 !!! error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:   Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTyping20.errors.txt b/tests/baselines/reference/contextualTyping20.errors.txt
index 7fc6b9a5e13..6a843031ebc 100644
--- a/tests/baselines/reference/contextualTyping20.errors.txt
+++ b/tests/baselines/reference/contextualTyping20.errors.txt
@@ -1,7 +1,7 @@
 tests/cases/compiler/contextualTyping20.ts(1,36): error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-      Property 'name' does not exist on type '{ id: number; }'.
+      Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping20.ts (1 errors) ====
@@ -10,4 +10,4 @@ tests/cases/compiler/contextualTyping20.ts(1,36): error TS2322: Type '({ id: num
 !!! error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
 !!! error TS2322:   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
 !!! error TS2322:     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:       Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:       Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTyping4.errors.txt b/tests/baselines/reference/contextualTyping4.errors.txt
index c2079cdf004..3749865e353 100644
--- a/tests/baselines/reference/contextualTyping4.errors.txt
+++ b/tests/baselines/reference/contextualTyping4.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/compiler/contextualTyping4.ts(1,13): error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-  Property 'name' does not exist on type '{ id: number; }'.
+  Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping4.ts (1 errors) ====
     class foo { public bar:{id:number;} = {id:5, name:"foo"}; }
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2322: Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:   Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTyping9.errors.txt b/tests/baselines/reference/contextualTyping9.errors.txt
index 45148e83a11..64c521d3f00 100644
--- a/tests/baselines/reference/contextualTyping9.errors.txt
+++ b/tests/baselines/reference/contextualTyping9.errors.txt
@@ -1,7 +1,7 @@
 tests/cases/compiler/contextualTyping9.ts(1,5): error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-      Property 'name' does not exist on type '{ id: number; }'.
+      Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
 
 
 ==== tests/cases/compiler/contextualTyping9.ts (1 errors) ====
@@ -10,4 +10,4 @@ tests/cases/compiler/contextualTyping9.ts(1,5): error TS2322: Type '({ id: numbe
 !!! error TS2322: Type '({ id: number; } | { id: number; name: string; })[]' is not assignable to type '{ id: number; }[]'.
 !!! error TS2322:   Type '{ id: number; } | { id: number; name: string; }' is not assignable to type '{ id: number; }'.
 !!! error TS2322:     Type '{ id: number; name: string; }' is not assignable to type '{ id: number; }'.
-!!! error TS2322:       Property 'name' does not exist on type '{ id: number; }'.
\ No newline at end of file
+!!! error TS2322:       Object literal may only specify known properties and 'name' does not exist in type '{ id: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.errors.txt b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.errors.txt
index 4a43ec56ead..97674ec7046 100644
--- a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.errors.txt
+++ b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/classes/propertyMemberDeclarations/memberFunctionDeclarations/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.ts(14,28): error TS2345: Argument of type '{ a: number; b: number; }' is not assignable to parameter of type '{ a: number; }'.
-  Property 'b' does not exist on type '{ a: number; }'.
+  Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
 
 
 ==== tests/cases/conformance/classes/propertyMemberDeclarations/memberFunctionDeclarations/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.ts (1 errors) ====
@@ -19,7 +19,7 @@ tests/cases/conformance/classes/propertyMemberDeclarations/memberFunctionDeclara
             var r2 = super.foo({ a: 1, b: 2 }); // { a: number }
                                ~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ a: number; b: number; }' is not assignable to parameter of type '{ a: number; }'.
-!!! error TS2345:   Property 'b' does not exist on type '{ a: number; }'.
+!!! error TS2345:   Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
             var r3 = this.foo({ a: 1, b: 2 }); // { a: number; b: number; }
         }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/destructuringParameterProperties5.errors.txt b/tests/baselines/reference/destructuringParameterProperties5.errors.txt
index 0f83063c936..29ae037bfa7 100644
--- a/tests/baselines/reference/destructuringParameterProperties5.errors.txt
+++ b/tests/baselines/reference/destructuringParameterProperties5.errors.txt
@@ -10,7 +10,7 @@ tests/cases/conformance/es6/destructuring/destructuringParameterProperties5.ts(7
 tests/cases/conformance/es6/destructuring/destructuringParameterProperties5.ts(11,16): error TS2345: Argument of type '[{ x1: number; x2: string; x3: boolean; }, string, boolean]' is not assignable to parameter of type '[{ x: number; y: string; z: boolean; }, number, string]'.
   Types of property '0' are incompatible.
     Type '{ x1: number; x2: string; x3: boolean; }' is not assignable to type '{ x: number; y: string; z: boolean; }'.
-      Property 'x1' does not exist on type '{ x: number; y: string; z: boolean; }'.
+      Object literal may only specify known properties and 'x1' does not exist in type '{ x: number; y: string; z: boolean; }'.
 
 
 ==== tests/cases/conformance/es6/destructuring/destructuringParameterProperties5.ts (10 errors) ====
@@ -47,5 +47,5 @@ tests/cases/conformance/es6/destructuring/destructuringParameterProperties5.ts(1
 !!! error TS2345: Argument of type '[{ x1: number; x2: string; x3: boolean; }, string, boolean]' is not assignable to parameter of type '[{ x: number; y: string; z: boolean; }, number, string]'.
 !!! error TS2345:   Types of property '0' are incompatible.
 !!! error TS2345:     Type '{ x1: number; x2: string; x3: boolean; }' is not assignable to type '{ x: number; y: string; z: boolean; }'.
-!!! error TS2345:       Property 'x1' does not exist on type '{ x: number; y: string; z: boolean; }'.
+!!! error TS2345:       Object literal may only specify known properties and 'x1' does not exist in type '{ x: number; y: string; z: boolean; }'.
     var [a_x1, a_x2, a_x3, a_y, a_z] = [a.x1, a.x2, a.x3, a.y, a.z];
\ No newline at end of file
diff --git a/tests/baselines/reference/incompatibleTypes.errors.txt b/tests/baselines/reference/incompatibleTypes.errors.txt
index 9da3b9a8c89..4f2c3f44011 100644
--- a/tests/baselines/reference/incompatibleTypes.errors.txt
+++ b/tests/baselines/reference/incompatibleTypes.errors.txt
@@ -19,9 +19,9 @@ tests/cases/compiler/incompatibleTypes.ts(42,5): error TS2345: Argument of type
     Type '() => string' is not assignable to type '(s: string) => number'.
       Type 'string' is not assignable to type 'number'.
 tests/cases/compiler/incompatibleTypes.ts(49,5): error TS2345: Argument of type '{ e: number; f: number; }' is not assignable to parameter of type '{ c: { b: string; }; d: string; }'.
-  Property 'e' does not exist on type '{ c: { b: string; }; d: string; }'.
+  Object literal may only specify known properties and 'e' does not exist in type '{ c: { b: string; }; d: string; }'.
 tests/cases/compiler/incompatibleTypes.ts(66,5): error TS2322: Type '{ e: number; f: number; }' is not assignable to type '{ a: { a: string; }; b: string; }'.
-  Property 'e' does not exist on type '{ a: { a: string; }; b: string; }'.
+  Object literal may only specify known properties and 'e' does not exist in type '{ a: { a: string; }; b: string; }'.
 tests/cases/compiler/incompatibleTypes.ts(72,5): error TS2322: Type 'number' is not assignable to type '() => string'.
 tests/cases/compiler/incompatibleTypes.ts(74,5): error TS2322: Type '(a: any) => number' is not assignable to type '() => any'.
 
@@ -103,7 +103,7 @@ tests/cases/compiler/incompatibleTypes.ts(74,5): error TS2322: Type '(a: any) =>
     of1({ e: 0, f: 0 });
         ~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ e: number; f: number; }' is not assignable to parameter of type '{ c: { b: string; }; d: string; }'.
-!!! error TS2345:   Property 'e' does not exist on type '{ c: { b: string; }; d: string; }'.
+!!! error TS2345:   Object literal may only specify known properties and 'e' does not exist in type '{ c: { b: string; }; d: string; }'.
     
     interface IMap {
      [key:string]:string;
@@ -123,7 +123,7 @@ tests/cases/compiler/incompatibleTypes.ts(74,5): error TS2322: Type '(a: any) =>
     var o1: { a: { a: string; }; b: string; } = { e: 0, f: 0 };
         ~~
 !!! error TS2322: Type '{ e: number; f: number; }' is not assignable to type '{ a: { a: string; }; b: string; }'.
-!!! error TS2322:   Property 'e' does not exist on type '{ a: { a: string; }; b: string; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'e' does not exist in type '{ a: { a: string; }; b: string; }'.
     
     var a1 = [{ e: 0, f: 0 }, { e: 0, f: 0 }, { e: 0, g: 0 }];
     
diff --git a/tests/baselines/reference/logicalOrExpressionIsContextuallyTyped.errors.txt b/tests/baselines/reference/logicalOrExpressionIsContextuallyTyped.errors.txt
index cd0497b3bff..645428fc627 100644
--- a/tests/baselines/reference/logicalOrExpressionIsContextuallyTyped.errors.txt
+++ b/tests/baselines/reference/logicalOrExpressionIsContextuallyTyped.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/conformance/expressions/binaryOperators/logicalOrOperator/logicalOrExpressionIsContextuallyTyped.ts(6,5): error TS2322: Type '{ a: string; b: number; } | { a: string; b: boolean; }' is not assignable to type '{ a: string; }'.
   Type '{ a: string; b: number; }' is not assignable to type '{ a: string; }'.
-    Property 'b' does not exist on type '{ a: string; }'.
+    Object literal may only specify known properties and 'b' does not exist in type '{ a: string; }'.
 
 
 ==== tests/cases/conformance/expressions/binaryOperators/logicalOrOperator/logicalOrExpressionIsContextuallyTyped.ts (1 errors) ====
@@ -13,4 +13,4 @@ tests/cases/conformance/expressions/binaryOperators/logicalOrOperator/logicalOrE
         ~
 !!! error TS2322: Type '{ a: string; b: number; } | { a: string; b: boolean; }' is not assignable to type '{ a: string; }'.
 !!! error TS2322:   Type '{ a: string; b: number; }' is not assignable to type '{ a: string; }'.
-!!! error TS2322:     Property 'b' does not exist on type '{ a: string; }'.
\ No newline at end of file
+!!! error TS2322:     Object literal may only specify known properties and 'b' does not exist in type '{ a: string; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/objectLitStructuralTypeMismatch.errors.txt b/tests/baselines/reference/objectLitStructuralTypeMismatch.errors.txt
index e263b971561..487d78a0b17 100644
--- a/tests/baselines/reference/objectLitStructuralTypeMismatch.errors.txt
+++ b/tests/baselines/reference/objectLitStructuralTypeMismatch.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/objectLitStructuralTypeMismatch.ts(2,5): error TS2322: Type '{ b: number; }' is not assignable to type '{ a: number; }'.
-  Property 'b' does not exist on type '{ a: number; }'.
+  Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
 
 
 ==== tests/cases/compiler/objectLitStructuralTypeMismatch.ts (1 errors) ====
@@ -7,4 +7,4 @@ tests/cases/compiler/objectLitStructuralTypeMismatch.ts(2,5): error TS2322: Type
     var x: { a: number; } = { b: 5 };
         ~
 !!! error TS2322: Type '{ b: number; }' is not assignable to type '{ a: number; }'.
-!!! error TS2322:   Property 'b' does not exist on type '{ a: number; }'.
\ No newline at end of file
+!!! error TS2322:   Object literal may only specify known properties and 'b' does not exist in type '{ a: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/objectLiteralFunctionArgContextualTyping.errors.txt b/tests/baselines/reference/objectLiteralFunctionArgContextualTyping.errors.txt
index c4b05fe9c49..89786f1dbfc 100644
--- a/tests/baselines/reference/objectLiteralFunctionArgContextualTyping.errors.txt
+++ b/tests/baselines/reference/objectLiteralFunctionArgContextualTyping.errors.txt
@@ -1,7 +1,7 @@
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping.ts(8,4): error TS2345: Argument of type '{ hello: number; }' is not assignable to parameter of type 'I'.
-  Property 'hello' does not exist on type 'I'.
+  Object literal may only specify known properties and 'hello' does not exist in type 'I'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping.ts(10,4): error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I'.
-  Property 'what' does not exist on type 'I'.
+  Object literal may only specify known properties and 'what' does not exist in type 'I'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping.ts(11,4): error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I'.
   Property 'value' is missing in type '{ toString: (s: string) => string; }'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping.ts(12,4): error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I'.
@@ -20,12 +20,12 @@ tests/cases/compiler/objectLiteralFunctionArgContextualTyping.ts(13,36): error T
     f2({ hello: 1 }) // error 
        ~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ hello: number; }' is not assignable to parameter of type 'I'.
-!!! error TS2345:   Property 'hello' does not exist on type 'I'.
+!!! error TS2345:   Object literal may only specify known properties and 'hello' does not exist in type 'I'.
     f2({ value: '' }) // missing toString satisfied by Object's member
     f2({ value: '', what: 1 }) // missing toString satisfied by Object's member
        ~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I'.
-!!! error TS2345:   Property 'what' does not exist on type 'I'.
+!!! error TS2345:   Object literal may only specify known properties and 'what' does not exist in type 'I'.
     f2({ toString: (s) => s }) // error, missing property value from ArgsString
        ~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I'.
diff --git a/tests/baselines/reference/objectLiteralFunctionArgContextualTyping2.errors.txt b/tests/baselines/reference/objectLiteralFunctionArgContextualTyping2.errors.txt
index 6fdf156cadc..4e3a706509e 100644
--- a/tests/baselines/reference/objectLiteralFunctionArgContextualTyping2.errors.txt
+++ b/tests/baselines/reference/objectLiteralFunctionArgContextualTyping2.errors.txt
@@ -1,9 +1,9 @@
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(8,4): error TS2345: Argument of type '{ hello: number; }' is not assignable to parameter of type 'I2'.
-  Property 'hello' does not exist on type 'I2'.
+  Object literal may only specify known properties and 'hello' does not exist in type 'I2'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(9,4): error TS2345: Argument of type '{ value: string; }' is not assignable to parameter of type 'I2'.
   Property 'doStuff' is missing in type '{ value: string; }'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(10,4): error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I2'.
-  Property 'what' does not exist on type 'I2'.
+  Object literal may only specify known properties and 'what' does not exist in type 'I2'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(11,4): error TS2345: Argument of type '{ toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
   Property 'value' is missing in type '{ toString: (s: any) => any; }'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(12,4): error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I2'.
@@ -23,7 +23,7 @@ tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(13,4): error T
     f2({ hello: 1 }) 
        ~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ hello: number; }' is not assignable to parameter of type 'I2'.
-!!! error TS2345:   Property 'hello' does not exist on type 'I2'.
+!!! error TS2345:   Object literal may only specify known properties and 'hello' does not exist in type 'I2'.
     f2({ value: '' })
        ~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ value: string; }' is not assignable to parameter of type 'I2'.
@@ -31,7 +31,7 @@ tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(13,4): error T
     f2({ value: '', what: 1 }) 
        ~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I2'.
-!!! error TS2345:   Property 'what' does not exist on type 'I2'.
+!!! error TS2345:   Object literal may only specify known properties and 'what' does not exist in type 'I2'.
     f2({ toString: (s) => s }) 
        ~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
diff --git a/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentError.errors.txt b/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentError.errors.txt
index 36379f6e058..61e3289134a 100644
--- a/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentError.errors.txt
+++ b/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentError.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentError.ts(4,5): error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ b: string; id: number; }'.
-  Property 'name' does not exist on type '{ b: string; id: number; }'.
+  Object literal may only specify known properties and 'name' does not exist in type '{ b: string; id: number; }'.
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentError.ts(5,16): error TS1131: Property or signature expected.
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentError.ts(5,22): error TS2403: Subsequent variable declarations must have the same type.  Variable 'id' must be of type 'number', but here has type 'any'.
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentError.ts(5,25): error TS1128: Declaration or statement expected.
@@ -18,7 +18,7 @@ tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPr
     var person: { b: string; id: number } = { name, id };  // error
         ~~~~~~
 !!! error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ b: string; id: number; }'.
-!!! error TS2322:   Property 'name' does not exist on type '{ b: string; id: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type '{ b: string; id: number; }'.
     var person1: { name, id };  // error: can't use short-hand property assignment in type position
                    ~~~~
 !!! error TS1131: Property or signature expected.
diff --git a/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.errors.txt b/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.errors.txt
index 32f7733a22d..5352c28d27c 100644
--- a/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.errors.txt
+++ b/tests/baselines/reference/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.ts(4,5): error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ b: string; id: number; }'.
-  Property 'name' does not exist on type '{ b: string; id: number; }'.
+  Object literal may only specify known properties and 'name' does not exist in type '{ b: string; id: number; }'.
 tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPropertiesAssignmentErrorFromMissingIdentifier.ts(5,79): error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ name: number; id: string; }'.
   Types of property 'name' are incompatible.
     Type 'string' is not assignable to type 'number'.
@@ -18,7 +18,7 @@ tests/cases/conformance/es6/shorthandPropertyAssignment/objectLiteralShorthandPr
     var person: { b: string; id: number } = { name, id };  // error
         ~~~~~~
 !!! error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ b: string; id: number; }'.
-!!! error TS2322:   Property 'name' does not exist on type '{ b: string; id: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type '{ b: string; id: number; }'.
     function bar(name: string, id: number): { name: number, id: string } { return { name, id }; }  // error
                                                                                   ~~~~~~~~~~~~
 !!! error TS2322: Type '{ name: string; id: number; }' is not assignable to type '{ name: number; id: string; }'.
diff --git a/tests/baselines/reference/orderMattersForSignatureGroupIdentity.errors.txt b/tests/baselines/reference/orderMattersForSignatureGroupIdentity.errors.txt
index a07fbaa4730..85b63ff2ec1 100644
--- a/tests/baselines/reference/orderMattersForSignatureGroupIdentity.errors.txt
+++ b/tests/baselines/reference/orderMattersForSignatureGroupIdentity.errors.txt
@@ -1,8 +1,8 @@
 tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts(19,3): error TS2345: Argument of type '{ s: string; n: number; }' is not assignable to parameter of type '{ n: number; }'.
-  Property 's' does not exist on type '{ n: number; }'.
+  Object literal may only specify known properties and 's' does not exist in type '{ n: number; }'.
 tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts(22,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'w' must be of type 'A', but here has type 'C'.
 tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts(24,3): error TS2345: Argument of type '{ s: string; n: number; }' is not assignable to parameter of type '{ n: number; }'.
-  Property 's' does not exist on type '{ n: number; }'.
+  Object literal may only specify known properties and 's' does not exist in type '{ n: number; }'.
 
 
 ==== tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts (3 errors) ====
@@ -27,7 +27,7 @@ tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts(24,3): error TS234
     v({ s: "", n: 0 }).toLowerCase();
       ~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ s: string; n: number; }' is not assignable to parameter of type '{ n: number; }'.
-!!! error TS2345:   Property 's' does not exist on type '{ n: number; }'.
+!!! error TS2345:   Object literal may only specify known properties and 's' does not exist in type '{ n: number; }'.
     
     var w: A;
     var w: C;
@@ -37,4 +37,4 @@ tests/cases/compiler/orderMattersForSignatureGroupIdentity.ts(24,3): error TS234
     w({ s: "", n: 0 }).toLowerCase();
       ~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ s: string; n: number; }' is not assignable to parameter of type '{ n: number; }'.
-!!! error TS2345:   Property 's' does not exist on type '{ n: number; }'.
\ No newline at end of file
+!!! error TS2345:   Object literal may only specify known properties and 's' does not exist in type '{ n: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/switchStatements.errors.txt b/tests/baselines/reference/switchStatements.errors.txt
index 09a799cc5cb..b20a0b604f9 100644
--- a/tests/baselines/reference/switchStatements.errors.txt
+++ b/tests/baselines/reference/switchStatements.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/statements/switchStatements/switchStatements.ts(35,10): error TS2322: Type '{ id: number; name: string; }' is not assignable to type 'C'.
-  Property 'name' does not exist on type 'C'.
+  Object literal may only specify known properties and 'name' does not exist in type 'C'.
 
 
 ==== tests/cases/conformance/statements/switchStatements/switchStatements.ts (1 errors) ====
@@ -40,7 +40,7 @@ tests/cases/conformance/statements/switchStatements/switchStatements.ts(35,10):
         case { id: 12, name: '' }:
              ~~~~~~~~~~~~~~~~~~~~
 !!! error TS2322: Type '{ id: number; name: string; }' is not assignable to type 'C'.
-!!! error TS2322:   Property 'name' does not exist on type 'C'.
+!!! error TS2322:   Object literal may only specify known properties and 'name' does not exist in type 'C'.
         case new C():
     }
     
diff --git a/tests/baselines/reference/symbolProperty21.errors.txt b/tests/baselines/reference/symbolProperty21.errors.txt
index 5bc0e20f75f..1d20e356b43 100644
--- a/tests/baselines/reference/symbolProperty21.errors.txt
+++ b/tests/baselines/reference/symbolProperty21.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/Symbols/symbolProperty21.ts(8,5): error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: boolean; }' is not assignable to parameter of type 'I<boolean, string>'.
-  Property '[Symbol.toPrimitive]' does not exist on type 'I<boolean, string>'.
+  Object literal may only specify known properties and '[Symbol.toPrimitive]' does not exist in type 'I<boolean, string>'.
 
 
 ==== tests/cases/conformance/es6/Symbols/symbolProperty21.ts (1 errors) ====
@@ -21,4 +21,4 @@ tests/cases/conformance/es6/Symbols/symbolProperty21.ts(8,5): error TS2345: Argu
     });
     ~
 !!! error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: boolean; }' is not assignable to parameter of type 'I<boolean, string>'.
-!!! error TS2345:   Property '[Symbol.toPrimitive]' does not exist on type 'I<boolean, string>'.
\ No newline at end of file
+!!! error TS2345:   Object literal may only specify known properties and '[Symbol.toPrimitive]' does not exist in type 'I<boolean, string>'.
\ No newline at end of file
diff --git a/tests/baselines/reference/taggedTemplateStringsTypeArgumentInference.errors.txt b/tests/baselines/reference/taggedTemplateStringsTypeArgumentInference.errors.txt
index 055cb4c756a..0bfeeb35ec9 100644
--- a/tests/baselines/reference/taggedTemplateStringsTypeArgumentInference.errors.txt
+++ b/tests/baselines/reference/taggedTemplateStringsTypeArgumentInference.errors.txt
@@ -2,7 +2,7 @@ tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference
   Type argument candidate 'string' is not a valid type argument because it is not a supertype of candidate 'number'.
 tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference.ts(77,11): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-    Property 'y' does not exist on type '{ x: number; z: Date; }'.
+    Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
 
 
 ==== tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference.ts (2 errors) ====
@@ -89,7 +89,7 @@ tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference
               ~~~~~~~~~~~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-!!! error TS2453:     Property 'y' does not exist on type '{ x: number; z: Date; }'.
+!!! error TS2453:     Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
     var a9e: {};
     
     // Generic tag with multiple parameters of generic type passed arguments with a single best common type
diff --git a/tests/baselines/reference/taggedTemplateStringsTypeArgumentInferenceES6.errors.txt b/tests/baselines/reference/taggedTemplateStringsTypeArgumentInferenceES6.errors.txt
index d3ef0a25425..98e7141322d 100644
--- a/tests/baselines/reference/taggedTemplateStringsTypeArgumentInferenceES6.errors.txt
+++ b/tests/baselines/reference/taggedTemplateStringsTypeArgumentInferenceES6.errors.txt
@@ -2,7 +2,7 @@ tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference
   Type argument candidate 'string' is not a valid type argument because it is not a supertype of candidate 'number'.
 tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInferenceES6.ts(76,11): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-    Property 'y' does not exist on type '{ x: number; z: Date; }'.
+    Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
 
 
 ==== tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInferenceES6.ts (2 errors) ====
@@ -88,7 +88,7 @@ tests/cases/conformance/es6/templates/taggedTemplateStringsTypeArgumentInference
               ~~~~~~~~~~~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-!!! error TS2453:     Property 'y' does not exist on type '{ x: number; z: Date; }'.
+!!! error TS2453:     Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
     var a9e: {};
     
     // Generic tag with multiple parameters of generic type passed arguments with a single best common type
diff --git a/tests/baselines/reference/typeArgInference2.errors.txt b/tests/baselines/reference/typeArgInference2.errors.txt
index 8711913e7ab..453fb57afb3 100644
--- a/tests/baselines/reference/typeArgInference2.errors.txt
+++ b/tests/baselines/reference/typeArgInference2.errors.txt
@@ -1,6 +1,6 @@
 tests/cases/compiler/typeArgInference2.ts(12,10): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ name: string; a: number; }' is not a valid type argument because it is not a supertype of candidate '{ name: string; b: number; }'.
-    Property 'b' does not exist on type '{ name: string; a: number; }'.
+    Object literal may only specify known properties and 'b' does not exist in type '{ name: string; a: number; }'.
 
 
 ==== tests/cases/compiler/typeArgInference2.ts (1 errors) ====
@@ -19,4 +19,4 @@ tests/cases/compiler/typeArgInference2.ts(12,10): error TS2453: The type argumen
              ~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ name: string; a: number; }' is not a valid type argument because it is not a supertype of candidate '{ name: string; b: number; }'.
-!!! error TS2453:     Property 'b' does not exist on type '{ name: string; a: number; }'.
\ No newline at end of file
+!!! error TS2453:     Object literal may only specify known properties and 'b' does not exist in type '{ name: string; a: number; }'.
\ No newline at end of file
diff --git a/tests/baselines/reference/typeArgumentInference.errors.txt b/tests/baselines/reference/typeArgumentInference.errors.txt
index d74ea9a2830..9bda4629b3a 100644
--- a/tests/baselines/reference/typeArgumentInference.errors.txt
+++ b/tests/baselines/reference/typeArgumentInference.errors.txt
@@ -2,9 +2,9 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInference.ts(68,11
   Type argument candidate 'string' is not a valid type argument because it is not a supertype of candidate 'number'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInference.ts(82,11): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-    Property 'y' does not exist on type '{ x: number; z: Date; }'.
+    Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInference.ts(84,66): error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-  Property 'y' does not exist on type 'A92'.
+  Object literal may only specify known properties and 'y' does not exist in type 'A92'.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/typeArgumentInference.ts (3 errors) ====
@@ -96,12 +96,12 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInference.ts(84,66
               ~~~~~~~~~~~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ x: number; z: Date; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-!!! error TS2453:     Property 'y' does not exist on type '{ x: number; z: Date; }'.
+!!! error TS2453:     Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: Date; }'.
     var a9e: {};
     var a9f = someGenerics9<A92>(undefined, { x: 6, z: new Date() }, { x: 6, y: '' });
                                                                      ~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-!!! error TS2345:   Property 'y' does not exist on type 'A92'.
+!!! error TS2345:   Object literal may only specify known properties and 'y' does not exist in type 'A92'.
     var a9f: A92;
     
     // Generic call with multiple parameters of generic type passed arguments with a single best common type
diff --git a/tests/baselines/reference/typeArgumentInferenceConstructSignatures.errors.txt b/tests/baselines/reference/typeArgumentInferenceConstructSignatures.errors.txt
index 6d0cd4a6f47..6b964f64ee9 100644
--- a/tests/baselines/reference/typeArgumentInferenceConstructSignatures.errors.txt
+++ b/tests/baselines/reference/typeArgumentInferenceConstructSignatures.errors.txt
@@ -14,11 +14,11 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstruct
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts(118,9): error TS2304: Cannot find name 'Window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts(120,15): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ x: number; z: any; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-    Property 'y' does not exist on type '{ x: number; z: any; }'.
+    Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: any; }'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts(120,51): error TS2304: Cannot find name 'window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts(122,56): error TS2304: Cannot find name 'window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts(122,66): error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-  Property 'y' does not exist on type 'A92'.
+  Object literal may only specify known properties and 'y' does not exist in type 'A92'.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstructSignatures.ts (11 errors) ====
@@ -166,7 +166,7 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstruct
                   ~~~~~~~~~~~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ x: number; z: any; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-!!! error TS2453:     Property 'y' does not exist on type '{ x: number; z: any; }'.
+!!! error TS2453:     Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: any; }'.
                                                       ~~~~~~
 !!! error TS2304: Cannot find name 'window'.
     var a9e: {};
@@ -175,7 +175,7 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceConstruct
 !!! error TS2304: Cannot find name 'window'.
                                                                      ~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-!!! error TS2345:   Property 'y' does not exist on type 'A92'.
+!!! error TS2345:   Object literal may only specify known properties and 'y' does not exist in type 'A92'.
     var a9f: A92;
     
     // Generic call with multiple parameters of generic type passed arguments with a single best common type
diff --git a/tests/baselines/reference/typeArgumentInferenceWithConstraints.errors.txt b/tests/baselines/reference/typeArgumentInferenceWithConstraints.errors.txt
index 00e483ffed7..e8b728cab14 100644
--- a/tests/baselines/reference/typeArgumentInferenceWithConstraints.errors.txt
+++ b/tests/baselines/reference/typeArgumentInferenceWithConstraints.errors.txt
@@ -19,11 +19,11 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConst
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts(85,9): error TS2304: Cannot find name 'Window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts(87,11): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate '{ x: number; z: any; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-    Property 'y' does not exist on type '{ x: number; z: any; }'.
+    Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: any; }'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts(87,47): error TS2304: Cannot find name 'window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts(89,52): error TS2304: Cannot find name 'window'.
 tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts(89,62): error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-  Property 'y' does not exist on type 'A92'.
+  Object literal may only specify known properties and 'y' does not exist in type 'A92'.
 
 
 ==== tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConstraints.ts (16 errors) ====
@@ -148,7 +148,7 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConst
               ~~~~~~~~~~~~~
 !!! error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
 !!! error TS2453:   Type argument candidate '{ x: number; z: any; }' is not a valid type argument because it is not a supertype of candidate '{ x: number; y: string; }'.
-!!! error TS2453:     Property 'y' does not exist on type '{ x: number; z: any; }'.
+!!! error TS2453:     Object literal may only specify known properties and 'y' does not exist in type '{ x: number; z: any; }'.
                                                   ~~~~~~
 !!! error TS2304: Cannot find name 'window'.
     var a9e: {};
@@ -157,7 +157,7 @@ tests/cases/conformance/expressions/functionCalls/typeArgumentInferenceWithConst
 !!! error TS2304: Cannot find name 'window'.
                                                                  ~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ x: number; y: string; }' is not assignable to parameter of type 'A92'.
-!!! error TS2345:   Property 'y' does not exist on type 'A92'.
+!!! error TS2345:   Object literal may only specify known properties and 'y' does not exist in type 'A92'.
     var a9f: A92;
     
     // Generic call with multiple parameters of generic type passed arguments with a single best common type
diff --git a/tests/baselines/reference/typeInfer1.errors.txt b/tests/baselines/reference/typeInfer1.errors.txt
index e7653ecd3a5..c90345c7f45 100644
--- a/tests/baselines/reference/typeInfer1.errors.txt
+++ b/tests/baselines/reference/typeInfer1.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/typeInfer1.ts(11,5): error TS2322: Type '{ Moo: () => string; }' is not assignable to type 'ITextWriter2'.
-  Property 'Moo' does not exist on type 'ITextWriter2'.
+  Object literal may only specify known properties and 'Moo' does not exist in type 'ITextWriter2'.
 
 
 ==== tests/cases/compiler/typeInfer1.ts (1 errors) ====
@@ -16,6 +16,6 @@ tests/cases/compiler/typeInfer1.ts(11,5): error TS2322: Type '{ Moo: () => strin
     var yyyyyyyy: ITextWriter2 = {
         ~~~~~~~~
 !!! error TS2322: Type '{ Moo: () => string; }' is not assignable to type 'ITextWriter2'.
-!!! error TS2322:   Property 'Moo' does not exist on type 'ITextWriter2'.
+!!! error TS2322:   Object literal may only specify known properties and 'Moo' does not exist in type 'ITextWriter2'.
         Moo: function() { return "cow"; }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/typeMatch2.errors.txt b/tests/baselines/reference/typeMatch2.errors.txt
index 847cfbaf407..9925ca71fee 100644
--- a/tests/baselines/reference/typeMatch2.errors.txt
+++ b/tests/baselines/reference/typeMatch2.errors.txt
@@ -3,9 +3,9 @@ tests/cases/compiler/typeMatch2.ts(3,2): error TS2322: Type '{}' is not assignab
 tests/cases/compiler/typeMatch2.ts(4,5): error TS2322: Type '{ x: number; }' is not assignable to type '{ x: number; y: number; }'.
   Property 'y' is missing in type '{ x: number; }'.
 tests/cases/compiler/typeMatch2.ts(5,2): error TS2322: Type '{ x: number; y: number; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-  Property 'z' does not exist on type '{ x: number; y: number; }'.
+  Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
 tests/cases/compiler/typeMatch2.ts(6,5): error TS2322: Type '{ x: number; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-  Property 'z' does not exist on type '{ x: number; y: number; }'.
+  Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
 tests/cases/compiler/typeMatch2.ts(18,5): error TS2322: Type 'Animal[]' is not assignable to type 'Giraffe[]'.
   Type 'Animal' is not assignable to type 'Giraffe'.
     Property 'g' is missing in type 'Animal'.
@@ -14,7 +14,7 @@ tests/cases/compiler/typeMatch2.ts(22,5): error TS2322: Type '{ f1: number; f2:
     Type 'Animal[]' is not assignable to type 'Giraffe[]'.
       Type 'Animal' is not assignable to type 'Giraffe'.
 tests/cases/compiler/typeMatch2.ts(34,5): error TS2322: Type '{ x: number; y: any; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-  Property 'z' does not exist on type '{ x: number; y: number; }'.
+  Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
 tests/cases/compiler/typeMatch2.ts(35,5): error TS2322: Type '{ x: number; }' is not assignable to type '{ x: number; y: number; }'.
   Property 'y' is missing in type '{ x: number; }'.
 
@@ -33,11 +33,11 @@ tests/cases/compiler/typeMatch2.ts(35,5): error TS2322: Type '{ x: number; }' is
     	a = { x: 1, y: 2, z: 3 };
     	~
 !!! error TS2322: Type '{ x: number; y: number; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-!!! error TS2322:   Property 'z' does not exist on type '{ x: number; y: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
         a = { x: 1, z: 3 };  // error
         ~
 !!! error TS2322: Type '{ x: number; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-!!! error TS2322:   Property 'z' does not exist on type '{ x: number; y: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
     }
     
     class Animal { private a; }
@@ -77,7 +77,7 @@ tests/cases/compiler/typeMatch2.ts(35,5): error TS2322: Type '{ x: number; }' is
         a = { x: 1, y: _any, z:1 }; 
         ~
 !!! error TS2322: Type '{ x: number; y: any; z: number; }' is not assignable to type '{ x: number; y: number; }'.
-!!! error TS2322:   Property 'z' does not exist on type '{ x: number; y: number; }'.
+!!! error TS2322:   Object literal may only specify known properties and 'z' does not exist in type '{ x: number; y: number; }'.
         a = { x: 1 }; // error
         ~
 !!! error TS2322: Type '{ x: number; }' is not assignable to type '{ x: number; y: number; }'.