Intelligent Computing Practices
Many people recommend using a limited account when on the Internet so as to not install bad software. This is a good way of prevention, but it really doesn't tell you what you should avoid; there are plenty of things that can still go wrong even when on a limited account.
When receiving and replying to e-mail, check who has sent it and be sceptical of its legitimacy if it involves financial details. Banks do not send e-mails asking you for your account details, neither does Microsoft warn you about problems by e-mail, no companies ask you for their product's CD-Key.
When on public computers, refrain from saving passwords and usernames; be sure to sign out after each session and to clear the cache, cookies and URL's visited. Using Firefox creates a much more secure environment to explore the Internet. It can block pop-ups and doesn't have the security holes that hackers target within Internet Explorer. Only use one anti-virus and one firewall at the same time, as having two of a kind is really just a waste of resources as each program must check the data for itself just to reach the same result. Lastly it is most important to check for updates for your preventative programs regularly to combat new threats.
When you install a personal firewall, there usually aren't many settings to tweak as they come fairly secure 'out-of-the-box'. However anti-virus products can be tweaked heavily, usually involving a trade-off with protection and speed. Some anti-virus software can be configured to have different scanning levels with either low, medium or high. High is the most secure but it will take the longest time to analyse the files. Also, depending on your computer, you may not need all of the protection your anti-virus product automatically loads up. If you are still using Windows 9x, you could put your virus protection levels down to low, because no viri are written for it anymore.
Be careful if using another anti-spyware tool other than the ones that I mentioned, many of these programs are actually spyware themselves using clever tactics to make the user think it will help when it won't, so ideally use Spybot Search and Destroy or Lavasoft Ad-aware. If you choose to use both spyware products, don't be fooled into thinking Spybot Search and Destroy is actually spyware itself. Spybot creates dormant backups of the files it removes by default which other anti-spyware programs will then pick up as spyware. Generally, you do not need spyware / adware / malware to be backed up, so you could disable this option and prevent any issues.
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