Despite 95% of people claiming to use anti-virus software, almost 12 million people (24%) have still had their computer affected by a virus, hacker, malware or spyware in the past six months. Some 39% described the assault as causing a major disruption and a further 10% admit to suffering a deadly attack, rendering their computer unusable; 5% admit to having personal details stolen.

This might be explained by the type of content being accessed, with almost 9% admitting the attack came from an 'adult' website (12% of men admit to this compared to 4% of women). A fifth (19%) of people say the attack came from general surfing and 12% from opening unknown files. The Moneysupermarket study suggests five "top tips" on how to stay secure:

* Keep spyware and anti-virus software up to date and firewalls turned on

* Make sure you use any automatic spam filters/pop up blockers that your email provider may supply

* Do not open emails or attachments from addresses you do not recognise

* Be wary of downloading applications from sites such as facebook, they can be malware

* Make sure you use strong password combinations to protect any online accounts

We would also recommend making sure that your Internet connection is managed by a good broadband router, preferably with an built-in firewall and or anti-virus filter (secure your Wi-Fi links too). It's a good idea to make sure that you have a firewall running in software on your computer too. Similarly, not all anti-virus software is equal and a strong commercial package like Eset's NOD32 is often better than free alternatives.