I'm scared now. The "API Setup" and "Play" button no longer worked and the language was switched when I tried playing again. I don't want a virus :(

Virus detection is checking the file against a checksum. If somehow the build file contains this checksum anywhere, its marked as infected (which it is not). I think that may be the reason.
I just quickly rebuild the win version by upgrading my Unity Game Engine. Let me know if the new uploaded build solves the issue!