“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

just faced this error on android studio 2.1.2. solved by adding MAIN/LAUNCHER intent-filter to default activity in flavour manifest, though filter already was in default activity in default manifest. It even was in merged manifest, but studio can't found it until i duplicated filter in both manifests.