I've got word from a steam friend that Garry's Mod is currently infected with some sort of hack. I heard that it could get a hold of peoples steam passwords and get your information. Whether it's true or not, it's really screwing up Gmod as of now. To avoid this, DO NOT START GMOD! Until the problem is 100% resolved, do not even start gmod unless you want to risk EVERYTHING! Keep tabs on the big guns like Garry and go to Facepunch for any updates. That is all.

'Til All Are Safe