After recent virus and worm alerts, and since I'm getting several infected messages a day from readers, it's time again for a reminder about protecting your system against viruses.

SQL Slammer wasn't destructive but caused massive slowdowns on the Internet, mostly due to heavy traffic. When the announcement came out that it was an SQL server exploit, many readers probably thought "I don't use SQL, so I'm safe." While in some cases, this might be true, in this case anyone using MSDE (Microsoft Desktop Engine) was also affected. MDSE is a mini-SQL server that provides ODBC services to many applications, including Visio, Visual Basic, Office and Office Developer.

Rule #1: Don't glance at the headlines and think "It doesn't apply to me." Visit sites like http://www.sarc.com/ (or your Antivirus program's homepage) and http://www.microsoft.com/technet/security/default.asp to get the technical details on vulnerabilities. When friends send you email telling you about a virus, you'll probably want to look here also: http://www.vmyths.com/ to confirm it's not a hoax.

Always [always, always, always, always, always] use an antivirus program. Which program you choose is not necessarily what's important as long as they keep the virus definitions (also called signatures ) current. A week-old definitions is as bad as not using any antivirus program and not only does your antivirus provider need to keep their definitions files updated, you need to install them.

Rule #2: Check the date on your definition files. Norton Anti-virus displays this information when you double-click its tray icon, other programs should have a similar way to check the date. If your definitions are older than a week, manually check for updates and install them, then find out why your program is not automatically updating. If you use Windows XP, you need a password entered for task scheduler to run. http://support.microsoft.com/default.aspx?scid=kb;en-us;311119

When was the last time you checked Windows Update? You should make it a part of your routine, monthly in many cases, immediately when you hear reports of new virus. Use the Windows Update icon on your start menu or type http://www.windowsupdate.com in your browser and let it scan your system. Do this monthly, even if you have Windows automatically checking for updates. Always read about the update before installing it in some cases, you won't want to install non-critical updates. The same applies to Office Update, located at http://www.officeupdate.com/ProductUpdates/default.aspx.

Rule #3: Keep your system updated. Don't trust automatic updating features to work 100% of the time, confirm the updates were installed. All Internet Explorer updates are important, the update to version 6 is especially important. If you can't access attachments after upgrading to Outlook Express 6, hit forward and save the attachment or follow the steps on this site: http://www.omegageek.com/OESecurity.htm