diff --git a/ionic/components/app/app.ts b/ionic/components/app/app.ts
index 3fa9458f27..2da8bd7011 100644
--- a/ionic/components/app/app.ts
+++ b/ionic/components/app/app.ts
@@ -136,6 +136,9 @@ export class IonicApp {
    * @param {TODO} component  The component to register
    */
   register(key, component) {
+    if (this.components[key]) {
+      throw Error('Registered component key ' + key + ' already exists.');
+    }
     this.components[key] = component;
   }
 
diff --git a/ionic/components/menu/test/basic/main.html b/ionic/components/menu/test/basic/main.html
index 9d00a71b6a..9c59cfa68c 100644
--- a/ionic/components/menu/test/basic/main.html
+++ b/ionic/components/menu/test/basic/main.html
@@ -1,4 +1,4 @@
-<ion-menu #menu [content]="content" id="menu">
+<ion-menu #menu [content]="content">
 
   <ion-toolbar secondary>
     <ion-title>Left Menu</ion-title>
@@ -12,7 +12,7 @@
         {{p.title}}
       </button>
 
-      <button ion-item menu-toggle="menu" id="e2eCloseMenu">
+      <button ion-item menu-toggle id="e2eCloseMenu">
         Close Menu
       </button>