Whenever I try to join a server, it says I'm logged in elsewhere.

[BobIsAwesome]

It keeps doing this even after I've relogged in five times. I changed my password, and did a virus scan. I'm not being hijacked. What's the deal? I can play other games fine, but not Garry's Mod. Any tips or suggestions?

[editline]09:24PM[/editline]

I just confirmed that I can play Left 4 Dead 2 fine.

[Danneh]

Close steam then fo into steam directory and delete the file "Clientregistry.blob" then try garry's mod again

[gvazdas]

If what [B][URL="http://www.facepunch.com/member.php?u=80908"][B]djjkxboxd
[/B][/URL]Told you didn't work, means someone else has logged to your account. Maybe a friend or neighbor. If not - you got HAXD and must change your password and secret question!!!
[/B]

[BobIsAwesome]

[QUOTE=djjkxbox;19474998]Close steam then fo into steam directory and delete the file "Clientregistry.blob" then try garry's mod again[/QUOTE]

That fixed it, thanks.

[Divran]

[QUOTE=Gvazdas;19488866]If what [B][URL="http://www.facepunch.com/member.php?u=80908"][B]djjkxboxd
[/B][/URL]Told you didn't work, means someone else has logged to your account. Maybe a friend or neighbor. If not - you got HAXD and must change your password and secret question!!!
[/B][/QUOTE]

No it doesn't have to mean that.
I get this error every time I log on to my laptop for a while and then try to play on my PC again. What djjkxbox said fixes it.