Securing networked computer systems is a fairly complex subject and beyond the scope of these self help notes. If you need advice in this area, let us know.

However, every PC user needs an awareness of security issues and how to reduce the risk of intrusion, data theft or performance degradation.

Maintaining a secure system requires a combination of common sense and using a variety of readily available tools to prevent intrusion, scan for viruses and clean up possibly malignant files.

There is little point in investing time and money in anti-virus and other tools without adopting good practise in using your PC. Many of the Windows and Mac PC's we've had to fix, were used by clients' children, often sharing one login identity. Children and teenagers are attracted by all the applications that are most exploited by spyware, crackers and scam merchants: peer to peer sharing (music and video downloading), instant messanging (chat) and dodgy websites.

We recognise that people will use all these and therefore a few precautions are necessary to reduce the risk of intrusion or performance degradation.

Many threats are carried via email and you should avoid opening emails from untrusted sources or with dubious attachments; a list dangerouse file extensions is provided at: http://www.novatone.net/mag/mailsec.htm, together with further information on the nature of the threats. You shouldn't open emails with .scr or .pif suffix, for example, even if they come from someone you know; email addresses are often forged.

Checklist

• each user should have their own login and password and should be given restricted privileges. ie. in Windows no-one other than you should have administration privileges
• never give anyone else your password
• keep your anti-virus definitions up to date
• install anti-spyware and scan for spyware regularly and particularly after surfing the internet.
• Make sure you have a decent firewall
• Set the default in your web browser to block cookies and pop-ups