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Preventing viruses and worms

How can we prevent our computers from being affected by worms or viruses?
In recent years, the havoc wreaked by viruses, worms and breakins has been significant. Many malicious programs today are hybrids with characteristics of both viruses and worms. The program may initially infect a machine by being executed from an email attachment, but will then execute code which attempts to infect other systems via file sharing, or by exploiting vulnerabilities on the system and other networked computers. Unfortunately, viruses, worms and breakins are fairly commonplace and can wreak havoc on your computer's programs, operating system or data.

What you can do:

  • Install good anti-virus software, preferably a licensed copy so that you don't miss out on updates after the trial period.

  • Update your virus definitions regularly, ideally on a daily basis. Anti-virus software these days allow Live Update feature enabling the user to schedule the updates from vendor site.

  • Configure your anti-virus software to automatically scan every e-mail message for potential viruses.

  • Just as often, visit sites that document the latest threats to find out what subject lines and file-attachment names the newest viruses are using. For example: McAfee, Symantec, and Trend Micro are some of the sites providing up to date information on new threats.

  • Never miss out on the latest OS patches/updates. If you are a Windows user, then use Microsoft Windows update to download and install critical security patches.

  • E-mail is one of the popular medium of spreading viruses and worms. Be skeptical about e-mail attachments even from the known people. Look out for strange subject lines and if possible disable the preview feature.

  • Do not accept, download or execute any software from unknown sites.

  • Install Internet Connection Firewall (ICF) which blocks traffic -- except traffic that it considers being "normal." Many attacking programs use "normal" ports to spread through or to compromise a computer. Firewalls are helpful, but like other programs, they are not all encompassing. They should be used as part of a layered defense.

  • For all instant messaging software users -- my advice is to stay away from accepting any files unless it's from a trusted source. Since IM's do not check for viruses before downloading, there are greater chances of infecting your computer.

  • Turn off any unwanted services on your computer.
  • This was last published in February 2004

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