android bug in 4.9- Failed to open descriptor file '../../../GameProject7a/GameProject7a.uproject'

EDIT: Fixed after enabling google play and apk packaging, thought I already had this enabled.

I added some C++ code, went through a lot of crashes where I had to revert to earlier backups and upgraded UE from 4.8 to 4.9. Now when I launch it on android, I get that bug. Works fine in the editor of course.

Totally lost on how to fix it, any ideas?

I has same problem,too.
help me