Why signed android apk is not running on emulator

Question

I have made a signed apk of an android project. Whenever my client try to run it on the emulator, he faces the following error message:

D:\\Android\\android-sdk-         


        

Answer 1

In my case it was because I signed it on a machine running JDK 7. Downgrading to JDK 6 fixed the problem. Thanks java.lang.SecurityException when install apk for the suggestion!