I have been using Google Plugin for Eclipse to deploy my project to App Engine, and it has been working fine for over a year now. But a couple of days ago, he stopped working, and I can not find the reason. The project is still an App Engine project, but the Deploy Application button is disabled.
I have already reinstalled the entire Google plugin in Eclipse. I also added another GAE project, but then the button is still disabled. I managed to turn on the button once for loading, but I do not know what caused the inclusion.

Has anyone seen this before and any clue how to fix this?
EDIT: The button is on when I removed and re-added the App Engine SDK from the project build path. After deployment, the button is again disabled.
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