linux - Sample Android project not working because of: Debug Certificate expired

I am trying to run one of the sample projects that come with android (and I have tried many). I keep getting this error in eclipse's Problems window.

Error generating final archive: Debug Certificate expired on 10/24/12 7:27 AM com.example.android.mediafx.HelloEffects      Unknown Android Packaging Problem

Basically I import the project from the samples directory. Then I right click on the project and choose

Run As --> android project

Another symptom of the problem is that the project has a red x next to it, but no red x in any sub-directory or file.

Answer

Delete ~/.android/debug.keystore and try again. The ADT should generate new debug keystore with new certificate in it.