wtf is this?

I had this error in windows xp then i deleted xp and put windows 2000 now it bring me the same erros. I did everything from adware to avg. Plz tell me how to fix this crap.

It's not an "error". Notice how the popup dialog box is captioned Messenger Service and is sent from a user called "SECURITY"? It's a spam message sent from someone who has found your computer's IP address, or your IP chain. The sender clearly wants it to look like an authentic error message, and wants you to visit the address listed for a solution to the problem, which is clearly a bogus, and may infect your computer with real viruses/spyware.

So here's what you do:

1) Open up your control panel form the start menu and click Administrative Tools.

2) Start up Services from the Administrative Tools folder.

3) Scroll down to a service called Messenger and select it.

4) Stop the service. Voilà, no more spam messages, problem solved.