Another CSTRIKE error
 

It says when I try to join an internet game that I must have the custom installed or something... wtf does that even mean?

HELP!~

How about giving us the full error description instead of a two word summary. But if I'm to guess, then it could be that it's not finding your mod when joining? I dunno.

That would be my diagnosis DriveHappy.
Load up HL.exe, go to custom game(may be under Multiplayer, I forget), click Counter-Strike and click Activate and try then.
If not, uninstall the mod, reinstall the mod.