diff --git a/packages/flutter_tools/lib/src/run_hot.dart b/packages/flutter_tools/lib/src/run_hot.dart
index ec2e3e0..1e9b369 100644
--- a/packages/flutter_tools/lib/src/run_hot.dart
+++ b/packages/flutter_tools/lib/src/run_hot.dart
@@ -313,25 +313,23 @@
     _devFS = null;
   }
 
-  Future<Null> _launchInView(String entryPath,
-                             String packagesPath,
-                             String assetsDirectoryPath) async {
+  Future<Null> _launchInView(Uri entryUri,
+                             Uri packagesUri,
+                             Uri assetsDirectoryUri) async {
     FlutterView view = vmService.vm.mainView;
-    return view.runFromSource(entryPath, packagesPath, assetsDirectoryPath);
+    return view.runFromSource(entryUri, packagesUri, assetsDirectoryUri);
   }
 
   Future<Null> _launchFromDevFS(ApplicationPackage package,
                                 String mainScript) async {
-    String entryPath = fs.path.relative(mainScript, from: projectRootPath);
-    String deviceEntryPath =
-        _devFS.baseUri.resolve(entryPath).toFilePath();
-    String devicePackagesPath =
-        _devFS.baseUri.resolve('.packages').toFilePath();
-    String deviceAssetsDirectoryPath =
-        _devFS.baseUri.resolve(getAssetBuildDirectory()).toFilePath();
-    await _launchInView(deviceEntryPath,
-                        devicePackagesPath,
-                        deviceAssetsDirectoryPath);
+    String entryUri = fs.path.relative(mainScript, from: projectRootPath);
+    Uri deviceEntryUri = _devFS.baseUri.resolveUri(fs.path.toUri(entryUri));
+    Uri devicePackagesUri = _devFS.baseUri.resolve('.packages');
+    Uri deviceAssetsDirectoryUri =
+        _devFS.baseUri.resolveUri(fs.path.toUri(getAssetBuildDirectory()));
+    await _launchInView(deviceEntryUri,
+                        devicePackagesUri,
+                        deviceAssetsDirectoryUri);
   }
 
   Future<OperationResult> _restartFromSources() async {
diff --git a/packages/flutter_tools/lib/src/vmservice.dart b/packages/flutter_tools/lib/src/vmservice.dart
index 764196c..4355164 100644
--- a/packages/flutter_tools/lib/src/vmservice.dart
+++ b/packages/flutter_tools/lib/src/vmservice.dart
@@ -710,15 +710,16 @@
   }
 
   Future<ServiceMap> runInView(String viewId,
-                               String main,
-                               String packages,
-                               String assetsDirectory) {
+                               Uri main,
+                               Uri packages,
+                               Uri assetsDirectory) {
+    // TODO(goderbauer): Transfer Uri (instead of file path) when remote end supports it.
     return invokeRpc('_flutter.runInView',
                     params: <String, dynamic> {
                       'viewId': viewId,
-                      'mainScript': main,
-                      'packagesFile': packages,
-                      'assetDirectory': assetsDirectory
+                      'mainScript': main.toFilePath(windows: false),
+                      'packagesFile': packages.toFilePath(windows: false),
+                      'assetDirectory': assetsDirectory.toFilePath(windows: false)
                     });
   }
 
@@ -1024,9 +1025,9 @@
   }
 
   // TODO(johnmccutchan): Report errors when running failed.
-  Future<Null> runFromSource(String entryPath,
-                             String packagesPath,
-                             String assetsDirectoryPath) async {
+  Future<Null> runFromSource(Uri entryUri,
+                             Uri packagesUri,
+                             Uri assetsDirectoryUri) async {
     final String viewId = id;
     // When this completer completes the isolate is running.
     final Completer<Null> completer = new Completer<Null>();
@@ -1040,9 +1041,9 @@
       }
     });
     await owner.vm.runInView(viewId,
-                             entryPath,
-                             packagesPath,
-                             assetsDirectoryPath);
+                             entryUri,
+                             packagesUri,
+                             assetsDirectoryUri);
     await completer.future;
     await owner.vm.refreshViews();
     await subscription.cancel();