Another pseudo-virus (a pop-up that warns your system has a virus. When you click oK it installs a script that flags a virus (when it isn’t) and redirects your browser to their website so you can pay them to “remove” the virus) going around - Malware Defender 2009.

(Click picture for a full sized image in a new window)

Pseudo-viruses generally won’t harm your PC (that could get them into trouble) but will be quite the annoyance - IE will always go to their page telling you that you need to pay for their software and have them remove it.

If you get the above warning - DO NOT click OK. Click the little X in the top right corner to close the window (I do not know if clicking cancel will or will not install the virus - closing the window is the best way). I had this one pop up when I was looking at laptop bags at Nextag.com - I’ve already emailed the site administrators but generally sites don’t care about this since they are getting paid by the pseudo virus company (it popped up several times while I was at that site and didn’t pop up anywhere else).

I’ll do some research to see if I can find a cure for it but if you see it - DO NOT CLICK OK!

Update:
I found removal instructions:
http://www.2-spyware.com/remove-malware-defender-2009.html