Q I have the free AVG 7.5 anti-virus program, Ccleaner and the Windows Defender firewall. I am starting with broadband at the end of this month and I wondered if I could use the Zonealarm firewall (the free version) as well as Defender or should Defender be removed to allow Zonealarm to work? Also do you think I have enough protection, or should I buy another package? My computer is never left switched on.
M Taylor

A The three things you need for basic computer protection are an anti-virus program, a firewall and an anti-spyware program.

As Windows XP has a built-in firewall, you actually have all three installed at the moment, and there’s no need to duplicate them (in fact, it can cause problems to have, for instance, two firewalls running). Windows Defender is an anti-spyware program, not a firewall, so you can remove either this or Ccleaner, and still be fine.

Finally, AVG covers the anti-virus side of things. On the question of when the computer is switched on, it’s generally considered crucial to have all three of these programs running whenever the computer is switched on and connected to the internet, whether you’re using it or not – so even if it’s only in use for short periods, make sure all three are up-to-date and working.