This isn't specifically TF2 related (it's any game) so wasn't sure where to put it.
Since yesterday, my steam overlay has not been working. I have tried different binds and nothing has worked. So I decided to check the processes in task manager, and found out that it hasn't actually been launching when I've launched a game. I tried to launch it manually in the steam folder and got these lines
Tue Feb 02 07:34:23 2016 UTC - GameOverlay process started: pid: 8528
Tue Feb 02 07:34:23 2016 UTC - GameOverlay exiting due to missing PID argument
I have even re-installed steam, tried with and without skins.
I tried turning Windows Firewall off and it didn't do anything. I do not use any other antivirus or firewall software.
EDIT: also tried with AND without Steam Beta.
Anyone have any ideas?