Can't join any game

Whenever I try to join an online match, I find myself in an empty lobby. Only the leave button works.
Bot matches make my game crash when I click start game. Sometimes I even get a nice "Microsoft Windows is not responding" window.

Windows 8.1 if that matters, everything worked until some builds ago.

Screenshot:

Do you have any mods installed? If yes try to disable them all.

Nope, never installed one.

Interesting. Any firewall or anti-virus installed? If yes which one?

No firewall and I'm on DMZ (some games require that)
I have the default Windows Defender on.

PA don't need to open any ports on your side so it's doesn't mater. To be fair I not sure what might cause this behavior, but did you tried to check integrity of game files?

Yeah, no luck..