During compiling some Android projects using Eclipse I had regular problems with exporting signed apk file. It is a known problem and everyone has his own solution to fix the issue. For my projects where I included many apk libs or jar files (Actionbarsherlock, gson, etc…) every export was finished with result:

Conversion to Dalvik format failed with error 1
or my Eclipse crashed or the package was corrupted 🙂 It was very frustrating. It was not problem with Proguard. The solution is very simple. Before you start to create signed apk file you should:
- go to Project menu -> disable Build Automatically…
- after that Project -> Clean.. and clean all yours projects you use to create your apk ( uncheck Start a build immediately)

- and now right click on the project -> Android tools -> Export signed application package…
Works for me on my workstations with Windows. And you still have problems with that?