Cannot delete W32 F Sasser Worm from my computer?

I normally surf the net for the latest software, games and kind of stuff. Downloading and testing new games and software is my favorite time pass. Everything was working fine but now I think my personal computer is infected with W32 F Sasser Worm. I am trying to delete this worm from my computer but my antivirus is not able to delete this worm from my personal computer. I normally use free antivirus software available on the internet. So if possible suggest me antivirus software which are available for free.

If your antivirus software is detecting the W32 Sasser F Worm on your computer system then it must be able to delete this virus from your computer system. I think the problem is with the updates you must try to update your free antivirus software. By the way you have not mentioned which antivirus software you are using. Well I will suggest you to use AVG scan antivirus. You can download this software from its official site or just follow the below link for the antivirus software.
http://www.techarena.in/download/upd...efinitions.htm

W32 Sasser F Worm which is detected on your computer system is a kind of internet worm. Or in simple words it a network worm, this worm normally exploits code implementation vulnerability. What it does is that it scan the internet protocol address and infect un-patch the system, due to this your system becomes more vulnerable to other kind of threats. I will strongly suggest you to do not rely on free antivirus buy antivirus software.

There is a reason that you cannot delete this W32 Sasser F Worm from your personal computer because it copies itself to windows folder as napatch.exe. After that it modifies registry run section to load automatically on the next startup. This worm modifies the following registry
HKCU\Software\Microsoft\Windows\CurrentVersion\Run"napatch.exe"=%WINDOWS%\napatch.exe
If know how to modify the registry values you can edit this registry to get rid of this virus.

Actually this kind of worm cannot be deleted by the antivirus software, because this worm not only modifies the registry key value but it un-patch the security file. So the best method, to remove this worm from your personal computer is follow the link given below and update your security patch.
http://www.microsoft.com/technet/sec.../MS04-011.mspx
Download the updates according to your system requirement.

Thank you for your reply I got rid of this W32 Sasser F Worm problem. Now my system is working smoothly. I have followed the steps which you have mentioned. I have downloaded the security updates from the Microsoft’s official site, and then scanned my personal computer with the free version of avast antivirus. Not only this antivirus deleted W32 Sasser F Worm from my computer but also removed the other threats present in my personal computer. But I want to know the preventive measures for avoiding problem like these.

You must follow the following preventive measures to avoid the problem like these.
1. You must enable your firewall setting so that torjans cannot enter your personal computer.
2. Ensure that you have the latest version of antivirus software and do not forget to update these antivirus software.
3. Update all the application software and the operating system so that the bugs left in the previous version of operating system can be removed.
4. Do not download the attachment of email from unknown user.