There is a virus named 'brontok' in my pc how can i remove it?How does virus come in my pc

Plz tell me some software which is free and reliable...i hav norton antivirus and it is expired...please help...thanks

There is a virus named 'brontok' in my pc how can i remove it?How does virus come in my pc?mcaffee

Rontokbro or brontok virus is a rapidly spreading Internet worm that propagates by e-mail in messages with infected attachments. Once the user executes such an attachment, the parasite installs itself to the system and runs its spreading routine. It scans the entire system for e-mail addresses and sends itself there using own mail engine. Rontokbro modifies essential system settings in order to disable standard Windows tools such as the Registry Editor or Command Prompt. It also immediately restarts a computer when it detects certain software running. Such software can be various antivirus and anti-spyware programs, web browsers, programming tools and many other popular applications. Rontokbro may launch an attack against several well-known web sites. The worm's activity severely degrades overall system performance and Internet connection speed and causes general system instability. The parasite runs on every Windows startup.

To remove it, please check http://www.2-spyware.com/remove-rontokbr...

There is a virus named 'brontok' in my pc how can i remove it?How does virus come in my pc?norton antivirus 2007