What to do to stop the worm

How do I prevent Sasser infecting my computer?

Sasser exploits a loophole in versions of the Microsoft operating systems Windows XP and Windows 2000.

If you are running these systems on your PC, you need to go on to the Microsoft website and download a small program which will plug the loophole.

This program, called a 'patch', is available free of charge. Instructions are on the Microsoft website, at www.microsoft.com/security/

Microsoft has urged users to ensure they set their computer to automatically download any patches it issues.

If you have anti-virus software, you should keep it updated to ensure it can combat the latest viruses roaming the Internet.

Updates are available from the website of the company which designed the software.

Users are also advised to install a protective 'firewall' on to their computer. A firewall is an add-on which polices the boundaries of any computer or network.

How do I know if my computer is already infected?

An error message is displayed. Typically, the machine will repeatedly crash or re-start itself. It may also become very slow.

What do I do to get rid of it?

Microsoft and many security firms are offering free software tools on their websites which diagnose whether your machine is infected.

These tools will then be able to 'clean up' your computer and rid it of the Sasser program.

Among the anti- virus companies offering such tools are:

www.trendmicro-europe.com www.sophos.com

You should then install the patch from Microsoft, as described above, to stop your machine becoming re-infected.

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