“Conversion to Dalvik format failed with error 1” on external JAR

Question

In my Android application in Eclipse I get the following error.

UNEXPECTED TOP-LEVEL EXCEPTION:
java.lang.IllegalArgumentException: already add

Answer 1

Ran into this problem myself today. Cleaning and rebuild did not fix the problem. Deleting and reimporting the project didn't help either.

I finally traced it back to a bad additions to my .class file. I think this was added by the plugin tools when I was trying to fix another problem, removing it got rid of the "Conversion to Dalvik format failed with error 1" build error: