Beware IM Viruses

My computer is infected by a messenger virus. It was sent by an anonymous person on my im list. I left my IM turned on last night or every night. When I woke up this morning, my desktop was bombarted with pop-up windows. The pop-up window looks like this..
chatpr.org\ mkspkong@hotmail.com ...

The thing i hate about this is to find out the virus sent to my friends' im. Now, people are pissed at me. I have no idea who sent this malicious virus to me. If I find out, he's dead meat! I turned off my PC when I left home. I didn't have time to clean up. I'd have to do it later when i get home.

Please take note not to accept any files transfer from me. Thx!