Cannot deploy my apps since updating SDK tools today
<p>This morning I updated various SDK components from Eclipse. I think it was
- Android SDK or Platform tools
- Google APIs 17 update
- Android Support Library
- Google Play Services</p>

<p>Now, my apps won't deploy. They build ok (eventually, after an hour of reconfiguring and rebuilding) but now when I deploy to the device, I get the following:</p>

<pre><code> VFY: unable to find class referenced in signature (Landroid/support/v4/app/Fragment;)
 VFY: unable to find class referenced in signature (Landroid/support/v4/app/Fragment;)
 VFY: unable to find class referenced in signature (Landroid/support/v4/app/Fragment;)
 Unable to resolve superclass of Lcom/com/myapp/MainActivity; (81)
 Link of class 'Lcom/com/myapp/MainActivity;' failed
 VFY: replacing opcode 0x71 at 0x0006
 VFY: unable to find class referenced in signature (Landroid/support/v4/app/Fragment;)
 Unable to resolve superclass of Lcom/com/myapp/MainActivity; (81)
 Link of class 'Lcom/com/myapp/MainActivity;' failed
 Shutting down VM
 threadid=1: thread exiting with uncaught exception (group=0x40015560)
 FATAL EXCEPTION: main
 java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.myapp/com.myapp.MainActivity}: java.lang.ClassNotFoundException: com.myapp.MainActivity in loader dalvik.system.PathClassLoader[/data/app/com.myapp.apk]
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1680)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
    at android.app.ActivityThread.access$1500(ActivityThread.java:123)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:130)
    at android.app.ActivityThread.main(ActivityThread.java:3835)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
    at dalvik.system.NativeStart.main(Native Method)
 Caused by: java.lang.ClassNotFoundException: com.myapp.MainActivity in loader dalvik.system.PathClassLoader[/data/app/myapp.apk]
    at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:551)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
    at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1672)
    ... 11 more
</code></pre>

<p>Bear in mind that this project, and others, have been happily running for months, so this isn't just some daft error like the activity missing from the manifest file.</p>

<p>I'm really wishing I hadn't bothered with the update now... any ideas welcome!</p>
