If, despite all your precautions, your computer does pick up a virus or other malware infection you should deal with it as soon as possible.

Your antivirus software will have the facility to scan your computer for infections and neutralise them. Most commonly, an AV program will attempt to repair any infected files it finds and quarantine the infection. This usually means moving the file(s) to a safe location on your hard drive where they cannot do any harm. Of course, an AV program can only deal with infections it knows about, which is why it is important to keep it up to date.

Most AV and other anti-malware programs have the facility to run regular, scheduled scans. Setting them to do so is a good idea.

Occasionally a computer will get an infection that your protective software cannot deal with. This is probably the time to seek expert assistance. If you can identify the problem you could:

• join and consult one of the many on-line forums; many of them are run by enthusiasts who do not charge for their advice. Searching the internet for a solution (see below)  will often bring up links to these forums. My favourite is www.techmonkeys.co.uk but there are many others;
  
• search the internet for a solution. It is possible to find and download specialist programs written especially to deal with some of the more common "difficult" problems.