What does it mean when you have a black screen with a red letter warning phrase on it??

One day i was surfing the net and when I closed the browser I noticed that I had this black screen with red letters that read:

Warning! Spyware Threat has been detected on your PC. Your computer has several fatal errors due to apyware activity. Your IP address is #IP# and via this address an unauthorized access was gained by another computer. It is strongly recommended to install an antispyware software to close all security vulnerabilites.

When I went to change my desktop background, I noticed that it was saved into my backgrounds and when I tried to change it, the backgroud changed itself back to the black screen with that message on it. I have Norton antivirus 2007 and it says that my system is clean, no cookies, viruses, trojan horses or anything. So I can't understand why this popped up and how to get rid of it...can someone please help me with this topic???

What does it mean when you have a black screen with a red letter warning phrase on it??anti virus scan

It's something more than that failure of an antivirus called "Norton" can pick up.

You didn't say that you used an antispyware program. I recommend downloading Spybot Search %26 Destroy, AND Ad-Aware 2007 Free. Those two free antispyware programs should pick it up.

http://fileforum.betanews.com/detail/Spy...

http://www.lavasoftusa.com/software/adaw...