My pc connecting to a network changes its desktop autoically from blue to red and promo4&5 pops

when browsing a pop up of promo 4 and 5 comes and then the page shows itself, could this be a virus. I tried scanning through sophos antivirus but it could not detect anything

My pc connecting to a network changes its desktop autoically from blue to red and promo4%265 pops eve time?norton

There are several tools to remove Malware infections. There are many malicious fake anti-malware applications. Frequently this rogue software uses intentional false positives to convince the user that their system has been compromised and then demands money to remove these false threats. In extreme cases the false threats are actually the very trojans that advertise or even directly install the rogue program. Also ensure that your system is up-to-date with all patches and that you have a firewall installed and set up correctly.

Vcleaner from AVG is a specialised virus removal tool:

http://cotojo.wordpress.com/2008/03/12/v...

Malwarebytes anti malware:

http://cotojo.wordpress.com/2008/03/17/r...

Trojan and Worm Remover:

http://cotojo.wordpress.com/2008/03/07/t...

Windows Malicious Software Removal Tool:

http://www.microsoft.com/downloads/detai...

Finally, change your browser to Firefox, much safer and added protection:

http://www.mozilla-europe.org/en/product...