To the people in the antivirus software industry we are both customer and prisoner.

Like all insurance policies, sales are helped by promoting fear, and those protecting us can make more than those preying on us. Yet while the computer-safety industry is worth many millions, the reality is that there is no need to pay.

The fact is that rather than costing hundreds of pounds, professional protection software, sufficient for most home users, is available for nothing. Oh, and don’t worry, it is all legal.

Why software can be free

First, there are promotional freebies: software companies offer products gratis in the hope that they will become the standard for their type.

Then there is freeware, shareware and open-source software. Thousands of techies contribute to developing free software either as a hobby or to fight back against computing’s corporatisation by software companies.

If it is “open source”, the programme code is available for anyone to improve it, but support is limited.

With freeware, the developers don’t make the code open, and often request a donation. With shareware, if you don’t pay, it loses some functionality or an annoying reminder message pops up every time it is used.

Many pay £100 or more for Office software, yet there is a plethora of powerful alternatives available for nothing.

OpenOffice (openoffice.org), for example, is an “open source”, downloadable suite of programs, including writer, calc, impress, draw and base, which are roughly equivalent to Word, Excel, Powerpoint, Paint and Access.

It compares pretty well with Microsoft Office’s Home version, which would set you back £125 (or about £90 on eBay). It is also compatible with documents written and drawn up with the main Microsoft Office programmes.

Free antivirus software

Malware (malicious software) is the name for all the things that attack computers.

Viruses, worms and trojans are spread through the internet, e-mail or disks, and will damage your computer or replicate on it and send similar bugs to all your contacts, so never open unexpected e-mail attachments, especially from unknown senders.

Active, updated antivirus software to recognise current malware and reverse any previous damage is also necessary.

Buy it from one of the big operators, such as Symantec/Norton or McAfee, and it will cost roughly £50 a year. But there is also decent freeware available.

Grisoft’s AVG (http://free.grisoft.com) makes money by selling virus protection to small businesses, but it offers a free version to domestic users.

Avast (avast.com) is also free for noncommercial users and offers technical support via e-mail. With both, ensure that you regularly download the free updates, as these inform the software about new bugs — without it you are not protected.

Free antiadware

Pop-ups can be generated from adware software that has sneaked into your system. It often happens if you download software other than from its main source, so try to avoid that.

Lavasoft (lavasoftusa.com) offers home users an adware scanner free of charge.

To stop the pop-ups themselves, use the downloadable toolbars from both Google and MSN, although sometimes they block legitimate windows, too. Holding down CTRL while clicking links stops this.

Free antispyware

Spyware covertly gathers information from you, including e-mail addresses, credit-card details and passwords and sends these data on to someone else.

Spyware.com is free software to combat this, although it does request donations.

Microsoft and Lavasoft also offer free antispyware.

Other tips to keep your info safe

Microsoft combats hackers by regularly sending out free security updates. Either visit Mircrosoft’s website or go to your computer’s control panel and then the system file for the automatic updates section.

Don’t stay connected to the web unnecessarily. Hackers commonly target those who have been connected for long periods.

You should also ensure that your firewall is on. Firewalls are the software or hardware through which any data from the internet must pass.

Microsoft XP has its own firewall, which for the average user is sufficient. Free customisable firewalls are available from Comodo, Zonealarm and Kerio.

As a minimum, back up any files you would miss most. As well as saving to DVDs or CDs, there are limited free, online storage facilities like BT Vault or AOL X-Drive, although you need to log in regularly to keep them activated. Also, if you are going to install any software, always back up first.

Martin Lewis is the creator of Moneysavingexpert.com, a free website dedicated to showing people how to save money on anything and everything

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