diff --git a/build/gulpfile.vscode.js b/build/gulpfile.vscode.js
index 85600b61b2e..9f746ef72cb 100644
--- a/build/gulpfile.vscode.js
+++ b/build/gulpfile.vscode.js
@@ -135,7 +135,7 @@ const config = {
 		name: product.nameLong + ' document',
 		role: 'Editor',
 		ostypes: ["TEXT", "utxt", "TUTX", "****"],
-		extensions: ["ascx", "asp", "aspx", "bash", "bash_login", "bash_logout", "bash_profile", "bashrc", "bat", "bowerrc", "c", "cc", "clj", "cljs", "cljx", "clojure", "cmd", "code", "coffee", "config", "cpp", "cs", "cshtml", "csproj", "css", "csx", "ctp", "cxx", "dockerfile", "dot", "dtd", "editorconfig", "edn", "eyaml", "eyml", "fs", "fsi", "fsscript", "fsx", "gemspec", "gitattributes", "gitconfig", "gitignore", "go", "h", "handlebars", "hbs", "hh", "hpp", "htm", "html", "hxx", "ini", "jade", "jav", "java", "js", "jscsrc", "jshintrc", "jshtm", "json", "jsp", "less", "lua", "m", "makefile", "markdown", "md", "mdoc", "mdown", "mdtext", "mdtxt", "mdwn", "mkd", "mkdn", "ml", "mli", "php", "phtml", "pl", "pl6", "pm", "pm6", "pod", "pp", "profile", "properties", "ps1", "psd1", "psgi", "psm1", "py", "r", "rb", "rhistory", "rprofile", "rs", "rt", "scss", "sh", "shtml", "sql", "svg", "svgz", "t", "ts", "txt", "vb", "wxi", "wxl", "wxs", "xaml", "xcodeproj", "xcworkspace", "xml", "yaml", "yml", "zlogin", "zlogout", "zprofile", "zsh", "zshenv", "zshrc"],
+		extensions: ["ascx", "asp", "aspx", "bash", "bash_login", "bash_logout", "bash_profile", "bashrc", "bat", "bowerrc", "c", "cc", "clj", "cljs", "cljx", "clojure", "cmd", "code-workspace", "coffee", "config", "cpp", "cs", "cshtml", "csproj", "css", "csx", "ctp", "cxx", "dockerfile", "dot", "dtd", "editorconfig", "edn", "eyaml", "eyml", "fs", "fsi", "fsscript", "fsx", "gemspec", "gitattributes", "gitconfig", "gitignore", "go", "h", "handlebars", "hbs", "hh", "hpp", "htm", "html", "hxx", "ini", "jade", "jav", "java", "js", "jscsrc", "jshintrc", "jshtm", "json", "jsp", "less", "lua", "m", "makefile", "markdown", "md", "mdoc", "mdown", "mdtext", "mdtxt", "mdwn", "mkd", "mkdn", "ml", "mli", "php", "phtml", "pl", "pl6", "pm", "pm6", "pod", "pp", "profile", "properties", "ps1", "psd1", "psgi", "psm1", "py", "r", "rb", "rhistory", "rprofile", "rs", "rt", "scss", "sh", "shtml", "sql", "svg", "svgz", "t", "ts", "txt", "vb", "wxi", "wxl", "wxs", "xaml", "xcodeproj", "xcworkspace", "xml", "yaml", "yml", "zlogin", "zlogout", "zprofile", "zsh", "zshenv", "zshrc"],
 		iconFile: 'resources/darwin/code_file.icns'
 	}],
 	darwinBundleURLTypes: [{
diff --git a/build/win32/code.iss b/build/win32/code.iss
index 8d0a32c1b73..e5c3d9d2a46 100644
--- a/build/win32/code.iss
+++ b/build/win32/code.iss
@@ -164,11 +164,11 @@ Root: HKCR; Subkey: "{#RegValueName}.clojure"; ValueType: string; ValueName: "";
 Root: HKCR; Subkey: "{#RegValueName}.clojure\DefaultIcon"; ValueType: string; ValueName: ""; ValueData: "{app}\resources\app\resources\win32\code_file.ico"; Tasks: associatewithfiles
 Root: HKCR; Subkey: "{#RegValueName}.clojure\shell\open\command"; ValueType: string; ValueName: ""; ValueData: """{app}\{#ExeBasename}.exe"" ""%1"""; Tasks: associatewithfiles
 
-Root: HKCR; Subkey: ".code\OpenWithProgids"; ValueType: none; ValueName: "{#RegValueName}"; Flags: deletevalue uninsdeletevalue; Tasks: associatewithfiles
-Root: HKCR; Subkey: ".code\OpenWithProgids"; ValueType: string; ValueName: "{#RegValueName}.code"; ValueData: ""; Flags: uninsdeletevalue; Tasks: associatewithfiles
-Root: HKCR; Subkey: "{#RegValueName}.code"; ValueType: string; ValueName: ""; ValueData: "{cm:SourceFile,Code Workspace}"; Flags: uninsdeletekey; Tasks: associatewithfiles
-Root: HKCR; Subkey: "{#RegValueName}.code\DefaultIcon"; ValueType: string; ValueName: ""; ValueData: "{app}\resources\app\resources\win32\code_file.ico"; Tasks: associatewithfiles
-Root: HKCR; Subkey: "{#RegValueName}.code\shell\open\command"; ValueType: string; ValueName: ""; ValueData: """{app}\{#ExeBasename}.exe"" ""%1"""; Tasks: associatewithfiles
+Root: HKCR; Subkey: ".code-workspace\OpenWithProgids"; ValueType: none; ValueName: "{#RegValueName}"; Flags: deletevalue uninsdeletevalue; Tasks: associatewithfiles
+Root: HKCR; Subkey: ".code-workspace\OpenWithProgids"; ValueType: string; ValueName: "{#RegValueName}.code-workspace"; ValueData: ""; Flags: uninsdeletevalue; Tasks: associatewithfiles
+Root: HKCR; Subkey: "{#RegValueName}.code-workspace"; ValueType: string; ValueName: ""; ValueData: "{cm:SourceFile,Code Workspace}"; Flags: uninsdeletekey; Tasks: associatewithfiles
+Root: HKCR; Subkey: "{#RegValueName}.code-workspace\DefaultIcon"; ValueType: string; ValueName: ""; ValueData: "{app}\resources\app\resources\win32\code_file.ico"; Tasks: associatewithfiles
+Root: HKCR; Subkey: "{#RegValueName}.code-workspace\shell\open\command"; ValueType: string; ValueName: ""; ValueData: """{app}\{#ExeBasename}.exe"" ""%1"""; Tasks: associatewithfiles
 
 Root: HKCR; Subkey: ".coffee\OpenWithProgids"; ValueType: none; ValueName: "{#RegValueName}"; Flags: deletevalue uninsdeletevalue; Tasks: associatewithfiles
 Root: HKCR; Subkey: ".coffee\OpenWithProgids"; ValueType: string; ValueName: "{#RegValueName}.coffee"; ValueData: ""; Flags: uninsdeletevalue; Tasks: associatewithfiles
diff --git a/src/vs/platform/windows/common/windows.ts b/src/vs/platform/windows/common/windows.ts
index 3f5cf623503..d6679ffc984 100644
--- a/src/vs/platform/windows/common/windows.ts
+++ b/src/vs/platform/windows/common/windows.ts
@@ -189,11 +189,17 @@ export interface IOpenFileRequest {
 export interface IWindowConfiguration extends ParsedArgs, IOpenFileRequest {
 	appRoot: string;
 	execPath: string;
+	isInitialStartup?: boolean;
 
 	userEnv: IProcessEnvironment;
+	nodeCachedDataDir: string;
+
+	backupPath?: string;
+
+	workspace?: IWorkspaceIdentifier;
+	folderPath?: string;
 
 	isISOKeyboard?: boolean;
-
 	zoomLevel?: number;
 	fullscreen?: boolean;
 	highContrast?: boolean;
@@ -201,15 +207,7 @@ export interface IWindowConfiguration extends ParsedArgs, IOpenFileRequest {
 	backgroundColor?: string;
 	accessibilitySupport?: boolean;
 
-	isInitialStartup?: boolean;
-
 	perfStartTime?: number;
 	perfAppReady?: number;
 	perfWindowLoadTime?: number;
-
-	workspace?: IWorkspaceIdentifier;
-	folderPath?: string;
-	backupPath?: string;
-
-	nodeCachedDataDir: string;
 }
\ No newline at end of file
diff --git a/src/vs/platform/workspaces/common/workspaces.ts b/src/vs/platform/workspaces/common/workspaces.ts
index f3699b125b7..fbd476524d6 100644
--- a/src/vs/platform/workspaces/common/workspaces.ts
+++ b/src/vs/platform/workspaces/common/workspaces.ts
@@ -16,7 +16,7 @@ import { IEnvironmentService } from "vs/platform/environment/common/environment"
 export const IWorkspacesMainService = createDecorator<IWorkspacesMainService>('workspacesMainService');
 export const IWorkspacesService = createDecorator<IWorkspacesService>('workspacesService');
 
-export const WORKSPACE_EXTENSION = 'code';
+export const WORKSPACE_EXTENSION = 'code-workspace';
 
 export interface IWorkspaceIdentifier {
 	id: string;
diff --git a/src/vs/workbench/electron-browser/main.ts b/src/vs/workbench/electron-browser/main.ts
index 5b47bbfeb31..9118720b026 100644
--- a/src/vs/workbench/electron-browser/main.ts
+++ b/src/vs/workbench/electron-browser/main.ts
@@ -137,6 +137,7 @@ function createAndInitializeWorkspaceService(configuration: IWindowConfiguration
 	return validateWorkspacePath(configuration).then(() => {
 		const workspaceConfigPath = configuration.workspace ? configuration.workspace.configPath : null;
 		const workspaceService = (workspaceConfigPath || configuration.folderPath) ? new WorkspaceServiceImpl(workspaceConfigPath, configuration.folderPath, environmentService) : new EmptyWorkspaceServiceImpl(environmentService);
+
 		return workspaceService.initialize().then(() => workspaceService, error => new EmptyWorkspaceServiceImpl(environmentService));
 	});
 }