“Default Activity Not Found” on Android Studio upgrade

Question

I upgraded IntelliJ Idea from 12.0.4 to 12.10.

Now all the modules in my Android project give the error:

Error: Default Activity Not Found

Answer 1

1. Build -> Rebuild Project
2. File -> Invalidate Caches.. -> Invalidate and restart

It works for me. Rebuild project to make sure that no errors in project. Then we can invalidate cache.