title: Eclipse - Errors running builder 'Android Package Builder'
body: <p>I updated ADT from 22.x to the latest 23.x and now I'm getting the following error when trying to run the project:</p>
  
  <p><code>Errors occurred during the build.
  Errors running builder 'Android Package Builder' on project 'Sample-project-1'.
  com/android/utils/GrabProcessOutput$IProcessOutput</code></p>
  
  <p>Here's the error in the log:</p>
  
  <blockquote>
    <p>java.lang.NoClassDefFoundError: com/android/utils/GrabProcessOutput$IProcessOutput
      at com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.build(PostCompilerBuilder.java:212)
      at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:733)
      at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
      at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:206)
      at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:328)
      at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:403)
      at org.eclipse.core.internal.resources.Project$1.run(Project.java:618)
      at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2345)
      at org.eclipse.core.internal.resources.Project.internalBuild(Project.java:597)
      at org.eclipse.core.internal.resources.Project.build(Project.java:124)
      at com.android.ide.eclipse.adt.internal.project.ProjectHelper.doFullIncrementalDebugBuild(ProjectHelper.java:1143)
      at com.android.ide.eclipse.adt.internal.launch.LaunchConfigDelegate.launch(LaunchConfigDelegate.java:155)
      at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:858)
      at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:707)
      at org.eclipse.debug.internal.ui.DebugUIPlugin.buildAndLaunch(DebugUIPlugin.java:1018)
      at org.eclipse.debug.internal.ui.DebugUIPlugin$8.run(DebugUIPlugin.java:1222)
      at org.eclipse.core.internal.jobs.Worker.run(Worker.java:53)
    Caused by: java.lang.ClassNotFoundException: com.android.utils.GrabProcessOutput$IProcessOutput cannot be found by com.android.ide.eclipse.adt_23.0.2.1259578
      at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
      at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
      at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
      at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      ... 17 more</p>
  </blockquote>
  
  <p>Of course this is all gibberish to me.
  Why is this happening and how do I fix it?</p>