Something got screwed up when I disabled UAC completely, then used bcdedit DDISABLE_INTEGRITY_CHECK and TESTSIGN commands. Then Windows performed some kind of a repair during boot!! My CS:GO will not launch now. I believe it has to do with permissions and Windows Repair. Is there a way to fully restore all permissions to their defaults or fix my issue without running Windows Restore or Refresh? Is there a way to look up where the problem with CS:GO lies? It just will not launch, saying CS:GO has stopped working. I tried Win7, WinXP compatibility modes, and also running it as an admin... - no go! I think its OS issue, not CS:GO! Also, I used Tweaking.com Windows 8.1 2.5.1 Repair tool. It didn't do much good, but I hope a similar one exists that would help?!