Can't Play Multiplayer

Whenever I try to play multiplayer in gmod, a message pops up and says “Your steam account is already logged in on another computer. Please login” or something like that, but im not logged in anywhere else. And the thing is, HL2:deathmatch works fine. I’ve tried reinstalling Gmod but it still doesnt work.

Someone could be hacking you.

If someone else was using his account, HL2DM wouldn’t work hurf durf.

OP: Delete everything in your Steam folder except the steamapps folder and steam.exe, then restart Steam.

What if, by some weird chance, he was only getting hacked when trying to go online in GMod?

The chances of that are equal to my house getting hit by a firework within the next 5 minutes.

Which is pretty high since I’m aiming it at your house

It was more than 5 minutes. :3

It won’t light.