diff --git a/src/services/services.ts b/src/services/services.ts
index 1ed91381469..7b523d7e7ab 100644
--- a/src/services/services.ts
+++ b/src/services/services.ts
@@ -4594,6 +4594,7 @@ namespace ts {
                     // Enumerate the available files
                     const files = host.readDirectory(baseDirectory, extensions, /*exclude*/undefined, /*include*/["./*"]);
                     forEach(files, filePath => {
+                        filePath = normalizePath(filePath);
                         if (exclude && comparePaths(filePath, exclude, scriptPath, ignoreCase) === Comparison.EqualTo) {
                             return false;
                         }
@@ -4614,7 +4615,7 @@ namespace ts {
                     if (host.getDirectories) {
                         const directories = host.getDirectories(baseDirectory);
                         forEach(directories, d => {
-                            const directoryName = getBaseFileName(removeTrailingDirectorySeparator(d));
+                            const directoryName = getBaseFileName(normalizePath(d));
 
                             result.push({
                                 name: ensureTrailingDirectorySeparator(directoryName),
@@ -4755,6 +4756,7 @@ namespace ts {
                             const nestedFiles = host.readDirectory(visibleModule.moduleDir, supportedTypeScriptExtensions, /*exclude*/undefined, /*include*/["./*"]);
 
                             forEach(nestedFiles, (f) => {
+                                f = normalizePath(f);
                                 const nestedModule = removeFileExtension(getBaseFileName(f));
                                 nonRelativeModules.push(nestedModule);
                             });
@@ -4850,6 +4852,7 @@ namespace ts {
             function getCompletionEntriesFromDirectories(host: LanguageServiceHost, options: CompilerOptions, directory: string, result: ImportCompletionEntry[]) {
                 if (host.getDirectories && directoryProbablyExists(directory, host)) {
                     forEach(host.getDirectories(directory), typeDirectory => {
+                        typeDirectory = normalizePath(typeDirectory);
                         result.push(createCompletionEntryForModule(getBaseFileName(typeDirectory), ScriptElementKind.externalModuleName));
                     });
                 }
diff --git a/src/services/shims.ts b/src/services/shims.ts
index 9f4d9d24a43..70e4975ce45 100644
--- a/src/services/shims.ts
+++ b/src/services/shims.ts
@@ -67,7 +67,7 @@ namespace ts {
         getProjectVersion?(): string;
         useCaseSensitiveFileNames?(): boolean;
 
-        readDirectory(path: string, extensions?: string, exclude?: string, include?: string): string;
+        readDirectory(rootDir: string, extension: string, basePaths?: string, excludeEx?: string, includeFileEx?: string, includeDirEx?: string, depth?: number): string;
         readFile(path: string, encoding?: string): string;
         resolvePath(path: string): string;
         fileExists(path: string): boolean;
@@ -417,12 +417,17 @@ namespace ts {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));
         }
 
-        public readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[] {
+        public readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[], depth?: number): string[] {
+            const pattern = getFileMatcherPatterns(path, extensions, exclude, include,
+                this.shimHost.useCaseSensitiveFileNames(), this.shimHost.getCurrentDirectory());
             return JSON.parse(this.shimHost.readDirectory(
                 path,
-                extensions ? JSON.stringify(extensions) : undefined,
-                exclude ? JSON.stringify(exclude) : undefined,
-                include ? JSON.stringify(include) : undefined
+                JSON.stringify(extensions),
+                JSON.stringify(pattern.basePaths),
+                pattern.excludePattern,
+                pattern.includeFilePattern,
+                pattern.includeDirectoryPattern,
+                depth
             ));
         }