diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 630f459a2ec..8ae2eb242d9 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -1056,7 +1056,8 @@ namespace ts {
                         !checkAndReportErrorForMissingPrefix(errorLocation, name, nameArg) &&
                         !checkAndReportErrorForExtendingInterface(errorLocation) &&
                         !checkAndReportErrorForUsingTypeAsNamespace(errorLocation, name, meaning) &&
-                        !checkAndReportErrorForUsingTypeAsValue(errorLocation, name, meaning)) {
+                        !checkAndReportErrorForUsingTypeAsValue(errorLocation, name, meaning) &&
+                        !checkAndReportErrorForUsingNamespaceModuleAsValue(errorLocation, name, meaning))  {
                         error(errorLocation, nameNotFoundMessage, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
                     }
                 }
@@ -1200,6 +1201,24 @@ namespace ts {
             return false;
         }
 
+        function checkAndReportErrorForUsingNamespaceModuleAsValue(errorLocation: Node, name: string, meaning: SymbolFlags): boolean {
+            if (meaning & (SymbolFlags.Value & ~SymbolFlags.NamespaceModule & ~SymbolFlags.Type)) {
+                const symbol = resolveSymbol(resolveName(errorLocation, name, SymbolFlags.NamespaceModule & ~SymbolFlags.Value, /*nameNotFoundMessage*/undefined, /*nameArg*/ undefined));
+                if (symbol) {
+                    error(errorLocation, Diagnostics.Cannot_use_namespace_0_as_a_value, name);
+                    return true;
+                }
+            }
+            else if (meaning & (SymbolFlags.Type & ~SymbolFlags.NamespaceModule & ~SymbolFlags.Value)) {
+                const symbol = resolveSymbol(resolveName(errorLocation, name, SymbolFlags.NamespaceModule & ~SymbolFlags.Type, /*nameNotFoundMessage*/undefined, /*nameArg*/ undefined));
+                if (symbol) {
+                    error(errorLocation, Diagnostics.Cannot_use_namespace_0_as_a_type, name);
+                    return true;
+                }
+            }
+            return false;
+        }
+
         function checkResolvedBlockScopedVariable(result: Symbol, errorLocation: Node): void {
             Debug.assert(!!(result.flags & SymbolFlags.BlockScopedVariable || result.flags & SymbolFlags.Class || result.flags & SymbolFlags.Enum));
             // Block-scoped variables cannot be used before their definition
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 075d4247460..10dc25ef70e 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2099,6 +2099,14 @@
         "category": "Error",
         "code": 2707
     },
+    "Cannot use namespace '{0}' as a value.": {
+        "category": "Error",
+        "code": 2708
+    },
+    "Cannot use namespace '{0}' as a type.": {
+        "category": "Error",
+        "code": 2709
+    },
 
     "Import declaration '{0}' is using private name '{1}'.": {
         "category": "Error",
diff --git a/src/lib/es2015.collection.d.ts b/src/lib/es2015.collection.d.ts
index b2255dab881..038ed1ed58c 100644
--- a/src/lib/es2015.collection.d.ts
+++ b/src/lib/es2015.collection.d.ts
@@ -30,9 +30,9 @@ interface WeakMap<K extends object, V> {
 }
 
 interface WeakMapConstructor {
-    new (): WeakMap<any, any>;
+    new (): WeakMap<object, any>;
     new <K extends object, V>(entries?: [K, V][]): WeakMap<K, V>;
-    readonly prototype: WeakMap<any, any>;
+    readonly prototype: WeakMap<object, any>;
 }
 declare var WeakMap: WeakMapConstructor;
 
@@ -58,15 +58,15 @@ interface ReadonlySet<T> {
     readonly size: number;
 }
 
-interface WeakSet<T> {
+interface WeakSet<T extends object> {
     add(value: T): this;
     delete(value: T): boolean;
     has(value: T): boolean;
 }
 
 interface WeakSetConstructor {
-    new (): WeakSet<any>;
-    new <T>(values?: T[]): WeakSet<T>;
-    readonly prototype: WeakSet<any>;
+    new (): WeakSet<object>;
+    new <T extends object>(values?: T[]): WeakSet<T>;
+    readonly prototype: WeakSet<object>;
 }
 declare var WeakSet: WeakSetConstructor;
diff --git a/src/lib/es2015.core.d.ts b/src/lib/es2015.core.d.ts
index 283cf4917c5..9c84fc259c7 100644
--- a/src/lib/es2015.core.d.ts
+++ b/src/lib/es2015.core.d.ts
@@ -311,7 +311,7 @@ interface ObjectConstructor {
      * @param target The target object to copy to.
      * @param sources One or more source objects from which to copy properties
      */
-    assign(target: any, ...sources: any[]): any;
+    assign(target: object, ...sources: any[]): any;
 
     /**
      * Returns an array of all symbol properties found directly on object o.
diff --git a/src/lib/es2015.iterable.d.ts b/src/lib/es2015.iterable.d.ts
index e29b97e2d7b..d242d14b663 100644
--- a/src/lib/es2015.iterable.d.ts
+++ b/src/lib/es2015.iterable.d.ts
@@ -118,10 +118,10 @@ interface SetConstructor {
     new <T>(iterable: Iterable<T>): Set<T>;
 }
 
-interface WeakSet<T> { }
+interface WeakSet<T extends object> { }
 
 interface WeakSetConstructor {
-    new <T>(iterable: Iterable<T>): WeakSet<T>;
+    new <T extends object>(iterable: Iterable<T>): WeakSet<T>;
 }
 
 interface Promise<T> { }
@@ -145,7 +145,7 @@ interface PromiseConstructor {
 }
 
 declare namespace Reflect {
-    function enumerate(target: any): IterableIterator<any>;
+    function enumerate(target: object): IterableIterator<any>;
 }
 
 interface String {
diff --git a/src/lib/es2015.proxy.d.ts b/src/lib/es2015.proxy.d.ts
index 89f9ebf55c0..c1b7805bbcf 100644
--- a/src/lib/es2015.proxy.d.ts
+++ b/src/lib/es2015.proxy.d.ts
@@ -1,4 +1,4 @@
-interface ProxyHandler<T> {
+interface ProxyHandler<T extends object> {
     getPrototypeOf? (target: T): object | null;
     setPrototypeOf? (target: T, v: any): boolean;
     isExtensible? (target: T): boolean;
@@ -16,7 +16,7 @@ interface ProxyHandler<T> {
 }
 
 interface ProxyConstructor {
-    revocable<T>(target: T, handler: ProxyHandler<T>): { proxy: T; revoke: () => void; };
-    new <T>(target: T, handler: ProxyHandler<T>): T;
+    revocable<T extends object>(target: T, handler: ProxyHandler<T>): { proxy: T; revoke: () => void; };
+    new <T extends object>(target: T, handler: ProxyHandler<T>): T;
 }
 declare var Proxy: ProxyConstructor;
diff --git a/src/lib/es2015.reflect.d.ts b/src/lib/es2015.reflect.d.ts
index 2dc92c3bddb..83755e4c791 100644
--- a/src/lib/es2015.reflect.d.ts
+++ b/src/lib/es2015.reflect.d.ts
@@ -1,15 +1,15 @@
 declare namespace Reflect {
     function apply(target: Function, thisArgument: any, argumentsList: ArrayLike<any>): any;
     function construct(target: Function, argumentsList: ArrayLike<any>, newTarget?: any): any;
-    function defineProperty(target: any, propertyKey: PropertyKey, attributes: PropertyDescriptor): boolean;
-    function deleteProperty(target: any, propertyKey: PropertyKey): boolean;
-    function get(target: any, propertyKey: PropertyKey, receiver?: any): any;
-    function getOwnPropertyDescriptor(target: any, propertyKey: PropertyKey): PropertyDescriptor;
-    function getPrototypeOf(target: any): any;
-    function has(target: any, propertyKey: PropertyKey): boolean;
-    function isExtensible(target: any): boolean;
-    function ownKeys(target: any): Array<PropertyKey>;
-    function preventExtensions(target: any): boolean;
-    function set(target: any, propertyKey: PropertyKey, value: any, receiver?: any): boolean;
-    function setPrototypeOf(target: any, proto: any): boolean;
-}
\ No newline at end of file
+    function defineProperty(target: object, propertyKey: PropertyKey, attributes: PropertyDescriptor): boolean;
+    function deleteProperty(target: object, propertyKey: PropertyKey): boolean;
+    function get(target: object, propertyKey: PropertyKey, receiver?: any): any;
+    function getOwnPropertyDescriptor(target: object, propertyKey: PropertyKey): PropertyDescriptor;
+    function getPrototypeOf(target: object): object;
+    function has(target: object, propertyKey: PropertyKey): boolean;
+    function isExtensible(target: object): boolean;
+    function ownKeys(target: object): Array<PropertyKey>;
+    function preventExtensions(target: object): boolean;
+    function set(target: object, propertyKey: PropertyKey, value: any, receiver?: any): boolean;
+    function setPrototypeOf(target: object, proto: any): boolean;
+}
diff --git a/src/lib/es2015.symbol.wellknown.d.ts b/src/lib/es2015.symbol.wellknown.d.ts
index 578cf0acbc2..3d030f37d49 100644
--- a/src/lib/es2015.symbol.wellknown.d.ts
+++ b/src/lib/es2015.symbol.wellknown.d.ts
@@ -118,7 +118,7 @@ interface Set<T> {
     readonly [Symbol.toStringTag]: "Set";
 }
 
-interface WeakSet<T> {
+interface WeakSet<T extends object> {
     readonly [Symbol.toStringTag]: "WeakSet";
 }
 
diff --git a/tests/baselines/reference/InvalidNonInstantiatedModule.errors.txt b/tests/baselines/reference/InvalidNonInstantiatedModule.errors.txt
index 9fd7043faa6..bc8582debd9 100644
--- a/tests/baselines/reference/InvalidNonInstantiatedModule.errors.txt
+++ b/tests/baselines/reference/InvalidNonInstantiatedModule.errors.txt
@@ -1,5 +1,5 @@
-tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiatedModule.ts(5,9): error TS2304: Cannot find name 'M'.
-tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiatedModule.ts(7,15): error TS2304: Cannot find name 'M'.
+tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiatedModule.ts(5,9): error TS2708: Cannot use namespace 'M' as a value.
+tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiatedModule.ts(7,15): error TS2708: Cannot use namespace 'M' as a value.
 
 
 ==== tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiatedModule.ts (2 errors) ====
@@ -9,9 +9,9 @@ tests/cases/conformance/internalModules/moduleDeclarations/InvalidNonInstantiate
     
     var m = M; // Error, not instantiated can not be used as var
             ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     
     var x: typeof M; // Error only a namespace
                   ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/aliasOnMergedModuleInterface.errors.txt b/tests/baselines/reference/aliasOnMergedModuleInterface.errors.txt
index 009d405c0f5..66d9eebb3dd 100644
--- a/tests/baselines/reference/aliasOnMergedModuleInterface.errors.txt
+++ b/tests/baselines/reference/aliasOnMergedModuleInterface.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/aliasOnMergedModuleInterface_1.ts(5,16): error TS2304: Cannot find name 'foo'.
+tests/cases/compiler/aliasOnMergedModuleInterface_1.ts(5,16): error TS2708: Cannot use namespace 'foo' as a value.
 
 
 ==== tests/cases/compiler/aliasOnMergedModuleInterface_1.ts (1 errors) ====
@@ -8,7 +8,7 @@ tests/cases/compiler/aliasOnMergedModuleInterface_1.ts(5,16): error TS2304: Cann
     z.bar("hello"); // This should be ok
     var x: foo.A = foo.bar("hello"); // foo.A should be ok but foo.bar should be error
                    ~~~
-!!! error TS2304: Cannot find name 'foo'.
+!!! error TS2708: Cannot use namespace 'foo' as a value.
     
 ==== tests/cases/compiler/aliasOnMergedModuleInterface_0.ts (0 errors) ====
     declare module "foo"
diff --git a/tests/baselines/reference/assignToModule.errors.txt b/tests/baselines/reference/assignToModule.errors.txt
index 26121d72a05..0b8b6f27deb 100644
--- a/tests/baselines/reference/assignToModule.errors.txt
+++ b/tests/baselines/reference/assignToModule.errors.txt
@@ -1,8 +1,8 @@
-tests/cases/compiler/assignToModule.ts(2,1): error TS2304: Cannot find name 'A'.
+tests/cases/compiler/assignToModule.ts(2,1): error TS2708: Cannot use namespace 'A' as a value.
 
 
 ==== tests/cases/compiler/assignToModule.ts (1 errors) ====
     module A {}
     A = undefined; // invalid LHS
     ~
-!!! error TS2304: Cannot find name 'A'.
\ No newline at end of file
+!!! error TS2708: Cannot use namespace 'A' as a value.
\ No newline at end of file
diff --git a/tests/baselines/reference/assignmentToReferenceTypes.errors.txt b/tests/baselines/reference/assignmentToReferenceTypes.errors.txt
index 7e323479d57..5e42a2e79c6 100644
--- a/tests/baselines/reference/assignmentToReferenceTypes.errors.txt
+++ b/tests/baselines/reference/assignmentToReferenceTypes.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/assignmentToReferenceTypes.ts(5,1): error TS2304: Cannot find name 'M'.
+tests/cases/compiler/assignmentToReferenceTypes.ts(5,1): error TS2708: Cannot use namespace 'M' as a value.
 tests/cases/compiler/assignmentToReferenceTypes.ts(9,1): error TS2539: Cannot assign to 'C' because it is not a variable.
 tests/cases/compiler/assignmentToReferenceTypes.ts(13,1): error TS2539: Cannot assign to 'E' because it is not a variable.
 tests/cases/compiler/assignmentToReferenceTypes.ts(16,1): error TS2539: Cannot assign to 'f' because it is not a variable.
@@ -11,7 +11,7 @@ tests/cases/compiler/assignmentToReferenceTypes.ts(16,1): error TS2539: Cannot a
     }
     M = null;
     ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     
     class C {
     }
diff --git a/tests/baselines/reference/assignments.errors.txt b/tests/baselines/reference/assignments.errors.txt
index 86bbe75cd4b..cb8b7a17bdf 100644
--- a/tests/baselines/reference/assignments.errors.txt
+++ b/tests/baselines/reference/assignments.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(11,1): error TS2304: Cannot find name 'M'.
+tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(11,1): error TS2708: Cannot use namespace 'M' as a value.
 tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(14,1): error TS2539: Cannot assign to 'C' because it is not a variable.
 tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(17,1): error TS2539: Cannot assign to 'E' because it is not a variable.
 tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(18,3): error TS2540: Cannot assign to 'A' because it is a constant or a read-only property.
@@ -19,7 +19,7 @@ tests/cases/conformance/expressions/valuesAndReferences/assignments.ts(31,1): er
     module M { }
     M = null; // Error
     ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     
     class C { }
     C = null; // Error
diff --git a/tests/baselines/reference/defaultArgsInFunctionExpressions.errors.txt b/tests/baselines/reference/defaultArgsInFunctionExpressions.errors.txt
index b0b0f876be4..d46963caeed 100644
--- a/tests/baselines/reference/defaultArgsInFunctionExpressions.errors.txt
+++ b/tests/baselines/reference/defaultArgsInFunctionExpressions.errors.txt
@@ -5,7 +5,7 @@ tests/cases/compiler/defaultArgsInFunctionExpressions.ts(11,1): error TS2322: Ty
 tests/cases/compiler/defaultArgsInFunctionExpressions.ts(14,51): error TS2352: Type 'string' cannot be converted to type 'number'.
 tests/cases/compiler/defaultArgsInFunctionExpressions.ts(17,41): error TS2322: Type '""' is not assignable to type 'number'.
 tests/cases/compiler/defaultArgsInFunctionExpressions.ts(20,62): error TS2352: Type 'string' cannot be converted to type 'number'.
-tests/cases/compiler/defaultArgsInFunctionExpressions.ts(28,15): error TS2304: Cannot find name 'T'.
+tests/cases/compiler/defaultArgsInFunctionExpressions.ts(28,15): error TS2708: Cannot use namespace 'T' as a value.
 
 
 ==== tests/cases/compiler/defaultArgsInFunctionExpressions.ts (8 errors) ====
@@ -52,7 +52,7 @@ tests/cases/compiler/defaultArgsInFunctionExpressions.ts(28,15): error TS2304: C
     
     var f6 = (t = T) => { };
                   ~
-!!! error TS2304: Cannot find name 'T'.
+!!! error TS2708: Cannot use namespace 'T' as a value.
     var f7 = (t = U) => { return t; };
     
     f7().x;
\ No newline at end of file
diff --git a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.errors.txt b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.errors.txt
index 7635608f58e..276654562a1 100644
--- a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.errors.txt
+++ b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.errors.txt
@@ -15,7 +15,7 @@ tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenc
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(18,38): error TS2314: Generic type 'I<T>' requires 1 type argument(s).
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(20,17): error TS2689: Cannot extend an interface 'I'. Did you mean 'implements'?
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(23,21): error TS2314: Generic type 'I<T>' requires 1 type argument(s).
-tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(29,18): error TS2304: Cannot find name 'M'.
+tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(29,18): error TS2708: Cannot use namespace 'M' as a value.
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(30,24): error TS2314: Generic type 'E<T>' requires 1 type argument(s).
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(31,24): error TS2694: Namespace 'M' has no exported member 'C'.
 tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenceWithoutTypeArgument2.ts(33,22): error TS2314: Generic type 'I<T>' requires 1 type argument(s).
@@ -89,7 +89,7 @@ tests/cases/conformance/types/specifyingTypes/typeReferences/genericTypeReferenc
     
     class D2 extends M.C { }
                      ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     interface D3<T extends M.E> { }
                            ~~~
 !!! error TS2314: Generic type 'E<T>' requires 1 type argument(s).
diff --git a/tests/baselines/reference/importDeclWithClassModifiers.errors.txt b/tests/baselines/reference/importDeclWithClassModifiers.errors.txt
index e1b8867d069..1f545bb01f2 100644
--- a/tests/baselines/reference/importDeclWithClassModifiers.errors.txt
+++ b/tests/baselines/reference/importDeclWithClassModifiers.errors.txt
@@ -1,11 +1,11 @@
 tests/cases/compiler/importDeclWithClassModifiers.ts(5,8): error TS1044: 'public' modifier cannot appear on a module or namespace element.
-tests/cases/compiler/importDeclWithClassModifiers.ts(5,26): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithClassModifiers.ts(5,26): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithClassModifiers.ts(5,28): error TS2694: Namespace 'x' has no exported member 'c'.
 tests/cases/compiler/importDeclWithClassModifiers.ts(6,8): error TS1044: 'private' modifier cannot appear on a module or namespace element.
-tests/cases/compiler/importDeclWithClassModifiers.ts(6,27): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithClassModifiers.ts(6,27): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithClassModifiers.ts(6,29): error TS2694: Namespace 'x' has no exported member 'c'.
 tests/cases/compiler/importDeclWithClassModifiers.ts(7,8): error TS1044: 'static' modifier cannot appear on a module or namespace element.
-tests/cases/compiler/importDeclWithClassModifiers.ts(7,26): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithClassModifiers.ts(7,26): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithClassModifiers.ts(7,28): error TS2694: Namespace 'x' has no exported member 'c'.
 
 
@@ -18,21 +18,21 @@ tests/cases/compiler/importDeclWithClassModifiers.ts(7,28): error TS2694: Namesp
            ~~~~~~
 !!! error TS1044: 'public' modifier cannot appear on a module or namespace element.
                              ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                                ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     export private import b = x.c;
            ~~~~~~~
 !!! error TS1044: 'private' modifier cannot appear on a module or namespace element.
                               ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                                 ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     export static import c = x.c;
            ~~~~~~
 !!! error TS1044: 'static' modifier cannot appear on a module or namespace element.
                              ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                                ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     var b: a;
diff --git a/tests/baselines/reference/importDeclWithDeclareModifier.errors.txt b/tests/baselines/reference/importDeclWithDeclareModifier.errors.txt
index d69a88964cc..93619813aa2 100644
--- a/tests/baselines/reference/importDeclWithDeclareModifier.errors.txt
+++ b/tests/baselines/reference/importDeclWithDeclareModifier.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/importDeclWithDeclareModifier.ts(5,9): error TS1029: 'export' modifier must precede 'declare' modifier.
-tests/cases/compiler/importDeclWithDeclareModifier.ts(5,27): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithDeclareModifier.ts(5,27): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithDeclareModifier.ts(5,29): error TS2694: Namespace 'x' has no exported member 'c'.
 
 
@@ -12,7 +12,7 @@ tests/cases/compiler/importDeclWithDeclareModifier.ts(5,29): error TS2694: Names
             ~~~~~~
 !!! error TS1029: 'export' modifier must precede 'declare' modifier.
                               ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                                 ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     var b: a;
diff --git a/tests/baselines/reference/importDeclWithExportModifier.errors.txt b/tests/baselines/reference/importDeclWithExportModifier.errors.txt
index 56e9a159afb..2a5dbbf74ef 100644
--- a/tests/baselines/reference/importDeclWithExportModifier.errors.txt
+++ b/tests/baselines/reference/importDeclWithExportModifier.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/importDeclWithExportModifier.ts(5,19): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithExportModifier.ts(5,19): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithExportModifier.ts(5,21): error TS2694: Namespace 'x' has no exported member 'c'.
 
 
@@ -9,7 +9,7 @@ tests/cases/compiler/importDeclWithExportModifier.ts(5,21): error TS2694: Namesp
     }
     export import a = x.c;
                       ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                         ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     var b: a;
diff --git a/tests/baselines/reference/importDeclWithExportModifierAndExportAssignment.errors.txt b/tests/baselines/reference/importDeclWithExportModifierAndExportAssignment.errors.txt
index ff3c47e9f33..f9f683c502b 100644
--- a/tests/baselines/reference/importDeclWithExportModifierAndExportAssignment.errors.txt
+++ b/tests/baselines/reference/importDeclWithExportModifierAndExportAssignment.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/importDeclWithExportModifierAndExportAssignment.ts(5,19): error TS2304: Cannot find name 'x'.
+tests/cases/compiler/importDeclWithExportModifierAndExportAssignment.ts(5,19): error TS2708: Cannot use namespace 'x' as a value.
 tests/cases/compiler/importDeclWithExportModifierAndExportAssignment.ts(5,21): error TS2694: Namespace 'x' has no exported member 'c'.
 tests/cases/compiler/importDeclWithExportModifierAndExportAssignment.ts(6,1): error TS2309: An export assignment cannot be used in a module with other exported elements.
 
@@ -10,7 +10,7 @@ tests/cases/compiler/importDeclWithExportModifierAndExportAssignment.ts(6,1): er
     }
     export import a = x.c;
                       ~
-!!! error TS2304: Cannot find name 'x'.
+!!! error TS2708: Cannot use namespace 'x' as a value.
                         ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     export = x;
diff --git a/tests/baselines/reference/importStatementsInterfaces.errors.txt b/tests/baselines/reference/importStatementsInterfaces.errors.txt
index 313365fb191..a43c368a2c2 100644
--- a/tests/baselines/reference/importStatementsInterfaces.errors.txt
+++ b/tests/baselines/reference/importStatementsInterfaces.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/conformance/internalModules/codeGeneration/importStatementsInterfaces.ts(23,19): error TS2304: Cannot find name 'a'.
+tests/cases/conformance/internalModules/codeGeneration/importStatementsInterfaces.ts(23,19): error TS2708: Cannot use namespace 'a' as a value.
 
 
 ==== tests/cases/conformance/internalModules/codeGeneration/importStatementsInterfaces.ts (1 errors) ====
@@ -26,7 +26,7 @@ tests/cases/conformance/internalModules/codeGeneration/importStatementsInterface
         import b = a.inA;
         var m: typeof a;
                       ~
-!!! error TS2304: Cannot find name 'a'.
+!!! error TS2708: Cannot use namespace 'a' as a value.
         var p: b.Point3D;
         var p = {x:0, y:0, z: 0 };
     }
diff --git a/tests/baselines/reference/interfaceNameAsIdentifier.errors.txt b/tests/baselines/reference/interfaceNameAsIdentifier.errors.txt
index 5be40b5b7b6..cc9cc927d0f 100644
--- a/tests/baselines/reference/interfaceNameAsIdentifier.errors.txt
+++ b/tests/baselines/reference/interfaceNameAsIdentifier.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/interfaceNameAsIdentifier.ts(4,1): error TS2693: 'C' only refers to a type, but is being used as a value here.
-tests/cases/compiler/interfaceNameAsIdentifier.ts(12,1): error TS2304: Cannot find name 'm2'.
+tests/cases/compiler/interfaceNameAsIdentifier.ts(12,1): error TS2708: Cannot use namespace 'm2' as a value.
 
 
 ==== tests/cases/compiler/interfaceNameAsIdentifier.ts (2 errors) ====
@@ -18,5 +18,5 @@ tests/cases/compiler/interfaceNameAsIdentifier.ts(12,1): error TS2304: Cannot fi
     
     m2.C();
     ~~
-!!! error TS2304: Cannot find name 'm2'.
+!!! error TS2708: Cannot use namespace 'm2' as a value.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/memberScope.errors.txt b/tests/baselines/reference/memberScope.errors.txt
index 017a28d5f71..7af426828db 100644
--- a/tests/baselines/reference/memberScope.errors.txt
+++ b/tests/baselines/reference/memberScope.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/compiler/memberScope.ts(4,11): error TS2304: Cannot find name 'Basil'.
+tests/cases/compiler/memberScope.ts(4,11): error TS2708: Cannot use namespace 'Basil' as a value.
 
 
 ==== tests/cases/compiler/memberScope.ts (1 errors) ====
@@ -7,7 +7,7 @@ tests/cases/compiler/memberScope.ts(4,11): error TS2304: Cannot find name 'Basil
       export module Basil { }
       var z = Basil.Pepper;
               ~~~~~
-!!! error TS2304: Cannot find name 'Basil'.
+!!! error TS2708: Cannot use namespace 'Basil' as a value.
     }
     
     
\ No newline at end of file
diff --git a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
index 716e84dadd0..a77fcd223f4 100644
--- a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
+++ b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
@@ -177,9 +177,9 @@ var p = new Proxy(t, {});
 // Using ES6 reflect
 Reflect.isExtensible({});
 >Reflect.isExtensible({}) : boolean
->Reflect.isExtensible : (target: any) => boolean
+>Reflect.isExtensible : (target: object) => boolean
 >Reflect : typeof Reflect
->isExtensible : (target: any) => boolean
+>isExtensible : (target: object) => boolean
 >{} : {}
 
 // Using Es6 regexp
diff --git a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
index d6c384b4280..6d5770659de 100644
--- a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
+++ b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
@@ -177,9 +177,9 @@ var p = new Proxy(t, {});
 // Using ES6 reflect
 Reflect.isExtensible({});
 >Reflect.isExtensible({}) : boolean
->Reflect.isExtensible : (target: any) => boolean
+>Reflect.isExtensible : (target: object) => boolean
 >Reflect : typeof Reflect
->isExtensible : (target: any) => boolean
+>isExtensible : (target: object) => boolean
 >{} : {}
 
 // Using Es6 regexp
diff --git a/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types b/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
index fe6cf35e596..9ca65cb9583 100644
--- a/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
+++ b/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
@@ -177,9 +177,9 @@ var p = new Proxy(t, {});
 // Using ES6 reflect
 Reflect.isExtensible({});
 >Reflect.isExtensible({}) : boolean
->Reflect.isExtensible : (target: any) => boolean
+>Reflect.isExtensible : (target: object) => boolean
 >Reflect : typeof Reflect
->isExtensible : (target: any) => boolean
+>isExtensible : (target: object) => boolean
 >{} : {}
 
 // Using Es6 regexp
diff --git a/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types b/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
index 440ca430a31..1120b471f36 100644
--- a/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
+++ b/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
@@ -100,9 +100,9 @@ var p = new Proxy(t, {});
 // Using ES6 reflect
 Reflect.isExtensible({});
 >Reflect.isExtensible({}) : boolean
->Reflect.isExtensible : (target: any) => boolean
+>Reflect.isExtensible : (target: object) => boolean
 >Reflect : typeof Reflect
->isExtensible : (target: any) => boolean
+>isExtensible : (target: object) => boolean
 >{} : {}
 
 // Using Es6 regexp
diff --git a/tests/baselines/reference/modularizeLibrary_UsingES5LibAndES6FeatureLibs.types b/tests/baselines/reference/modularizeLibrary_UsingES5LibAndES6FeatureLibs.types
index 281faddbc52..ab24aaf12ba 100644
--- a/tests/baselines/reference/modularizeLibrary_UsingES5LibAndES6FeatureLibs.types
+++ b/tests/baselines/reference/modularizeLibrary_UsingES5LibAndES6FeatureLibs.types
@@ -17,9 +17,9 @@ var p = new Proxy(t, {});
 
 Reflect.ownKeys({});
 >Reflect.ownKeys({}) : PropertyKey[]
->Reflect.ownKeys : (target: any) => PropertyKey[]
+>Reflect.ownKeys : (target: object) => PropertyKey[]
 >Reflect : typeof Reflect
->ownKeys : (target: any) => PropertyKey[]
+>ownKeys : (target: object) => PropertyKey[]
 >{} : {}
 
 function* idGen() {
diff --git a/tests/baselines/reference/moduleAsBaseType.errors.txt b/tests/baselines/reference/moduleAsBaseType.errors.txt
index ffa30ad0ab3..fd5b4f581f9 100644
--- a/tests/baselines/reference/moduleAsBaseType.errors.txt
+++ b/tests/baselines/reference/moduleAsBaseType.errors.txt
@@ -1,16 +1,16 @@
-tests/cases/compiler/moduleAsBaseType.ts(2,17): error TS2304: Cannot find name 'M'.
-tests/cases/compiler/moduleAsBaseType.ts(3,21): error TS2304: Cannot find name 'M'.
-tests/cases/compiler/moduleAsBaseType.ts(4,21): error TS2304: Cannot find name 'M'.
+tests/cases/compiler/moduleAsBaseType.ts(2,17): error TS2708: Cannot use namespace 'M' as a value.
+tests/cases/compiler/moduleAsBaseType.ts(3,21): error TS2709: Cannot use namespace 'M' as a type.
+tests/cases/compiler/moduleAsBaseType.ts(4,21): error TS2709: Cannot use namespace 'M' as a type.
 
 
 ==== tests/cases/compiler/moduleAsBaseType.ts (3 errors) ====
     module M {}
     class C extends M {}
                     ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2708: Cannot use namespace 'M' as a value.
     interface I extends M { }
                         ~
-!!! error TS2304: Cannot find name 'M'.
+!!! error TS2709: Cannot use namespace 'M' as a type.
     class C2 implements M { }
                         ~
-!!! error TS2304: Cannot find name 'M'.
\ No newline at end of file
+!!! error TS2709: Cannot use namespace 'M' as a type.
\ No newline at end of file
diff --git a/tests/baselines/reference/moduleWithNoValuesAsType.errors.txt b/tests/baselines/reference/moduleWithNoValuesAsType.errors.txt
index c387f5d62f4..21abac79217 100644
--- a/tests/baselines/reference/moduleWithNoValuesAsType.errors.txt
+++ b/tests/baselines/reference/moduleWithNoValuesAsType.errors.txt
@@ -1,20 +1,20 @@
-tests/cases/compiler/moduleWithNoValuesAsType.ts(2,8): error TS2304: Cannot find name 'A'.
-tests/cases/compiler/moduleWithNoValuesAsType.ts(7,8): error TS2304: Cannot find name 'B'.
-tests/cases/compiler/moduleWithNoValuesAsType.ts(15,8): error TS2304: Cannot find name 'C'.
+tests/cases/compiler/moduleWithNoValuesAsType.ts(2,8): error TS2709: Cannot use namespace 'A' as a type.
+tests/cases/compiler/moduleWithNoValuesAsType.ts(7,8): error TS2709: Cannot use namespace 'B' as a type.
+tests/cases/compiler/moduleWithNoValuesAsType.ts(15,8): error TS2709: Cannot use namespace 'C' as a type.
 
 
 ==== tests/cases/compiler/moduleWithNoValuesAsType.ts (3 errors) ====
     module A { }
     var a: A; // error
            ~
-!!! error TS2304: Cannot find name 'A'.
+!!! error TS2709: Cannot use namespace 'A' as a type.
     
     module B {
         interface I {}
     }
     var b: B; // error
            ~
-!!! error TS2304: Cannot find name 'B'.
+!!! error TS2709: Cannot use namespace 'B' as a type.
     
     module C {
         module M {
@@ -24,4 +24,4 @@ tests/cases/compiler/moduleWithNoValuesAsType.ts(15,8): error TS2304: Cannot fin
     
     var c: C; // error
            ~
-!!! error TS2304: Cannot find name 'C'.
\ No newline at end of file
+!!! error TS2709: Cannot use namespace 'C' as a type.
\ No newline at end of file
diff --git a/tests/baselines/reference/typeUsedAsValueError2.errors.txt b/tests/baselines/reference/typeUsedAsValueError2.errors.txt
index 3027abb0e6b..4aac95faa25 100644
--- a/tests/baselines/reference/typeUsedAsValueError2.errors.txt
+++ b/tests/baselines/reference/typeUsedAsValueError2.errors.txt
@@ -1,5 +1,5 @@
 tests/cases/compiler/world.ts(4,1): error TS2693: 'HelloInterface' only refers to a type, but is being used as a value here.
-tests/cases/compiler/world.ts(5,1): error TS2304: Cannot find name 'HelloNamespace'.
+tests/cases/compiler/world.ts(5,1): error TS2708: Cannot use namespace 'HelloNamespace' as a value.
 
 
 ==== tests/cases/compiler/world.ts (2 errors) ====
@@ -11,7 +11,7 @@ tests/cases/compiler/world.ts(5,1): error TS2304: Cannot find name 'HelloNamespa
 !!! error TS2693: 'HelloInterface' only refers to a type, but is being used as a value here.
     HelloNamespace.world;
     ~~~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'HelloNamespace'.
+!!! error TS2708: Cannot use namespace 'HelloNamespace' as a value.
 ==== tests/cases/compiler/helloInterface.ts (0 errors) ====
     interface HelloInterface {
         world: any;
diff --git a/tests/baselines/reference/typeofInternalModules.errors.txt b/tests/baselines/reference/typeofInternalModules.errors.txt
index c98456c3404..5402249ea63 100644
--- a/tests/baselines/reference/typeofInternalModules.errors.txt
+++ b/tests/baselines/reference/typeofInternalModules.errors.txt
@@ -1,8 +1,8 @@
-tests/cases/compiler/typeofInternalModules.ts(15,16): error TS2304: Cannot find name 'importUninst'.
+tests/cases/compiler/typeofInternalModules.ts(15,16): error TS2708: Cannot use namespace 'importUninst' as a value.
 tests/cases/compiler/typeofInternalModules.ts(17,9): error TS2304: Cannot find name 'Outer'.
 tests/cases/compiler/typeofInternalModules.ts(19,1): error TS2322: Type 'typeof Outer' is not assignable to type 'typeof instantiated'.
   Property 'C' is missing in type 'typeof Outer'.
-tests/cases/compiler/typeofInternalModules.ts(21,16): error TS2304: Cannot find name 'importUninst'.
+tests/cases/compiler/typeofInternalModules.ts(21,16): error TS2708: Cannot use namespace 'importUninst' as a value.
 tests/cases/compiler/typeofInternalModules.ts(23,1): error TS2322: Type 'typeof instantiated' is not assignable to type 'typeof Outer'.
   Property 'instantiated' is missing in type 'typeof instantiated'.
 
@@ -24,7 +24,7 @@ tests/cases/compiler/typeofInternalModules.ts(23,1): error TS2322: Type 'typeof
     var x2: importInst.C = new x1();
     var x3: typeof importUninst.P; // Error again
                    ~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'importUninst'.
+!!! error TS2708: Cannot use namespace 'importUninst' as a value.
     
     var x4: Outer = Outer;
             ~~~~~
@@ -37,7 +37,7 @@ tests/cases/compiler/typeofInternalModules.ts(23,1): error TS2322: Type 'typeof
     x5 = Outer.instantiated;
     var x6: typeof importUninst;
                    ~~~~~~~~~~~~
-!!! error TS2304: Cannot find name 'importUninst'.
+!!! error TS2708: Cannot use namespace 'importUninst' as a value.
     var x7: typeof Outer = Outer;
     x7 = importInst;
     ~~