Helping people with computers... one answer at a time.

Keeping the database of viruses that your anti-virus program uses up to date is critical. Here's why.

I currently use the free new version of AVG plus Zonealarm. Talking to a colleague at work the other day he mentioned he uses Norton because the AVG virus database is about 9 months out of date, implying that the auto updates I receive almost on a daily basis are very much out of date. Is this true and a consequence of going for a freebee? I have tried McAfee and couldn't get on with it at all.

I'll put it this way: if AVG free were 9 months out of date, you would have heard it from a lot more places than just a colleague. As it is, the free version of AVG is one of several reputable anti-virus programs recommended by many folks around the industry.

You do bring up a good point, though, that I want to take this opportunity to remind people about.

When they get a new computer, for example, they might start out nine months behind with any anti-virus program.

And that needs to be fixed.

Anti-virus programs have two parts: the program itself that knows how to scan your computer, and the database of viruses to look for.

While the program can remain relatively unchanging and still work well for you, the database cannot. New viruses are appearing every day, so it's important that the database be updated on a regular basis. Every nine months is not enough. In fact, every month is not enough, and every week is pushing it. If you're a relatively heavy computer and internet user I recommend making sure that your anti-virus database gets checked daily.

Why is this so important? Let's say you're updating weekly, on Sunday. On Monday a new virus is detected, and the anti-virus manufacturers put out updates to their database. Updates that, while available, you won't take until the following Sunday. In the mean time, the new virus is making its way around the internet, infecting unprotected machines. Come Friday or Saturday, a full five days after the database update, you're still vulnerable. Your machine could get infected. A week is an eternity on the internet. Had you been updating monthly? That's eons in internet time.

What I'll call "the nine month problem" can happen when you first install a an anti-virus program, or when you get a new machine with an anti-virus program pre-installed. That program, and the database that comes with it, are current as of the time you downloaded it, the time the CD it's on was created, or the time that the manufacturer got their master copy. That could be hours, days, weeks, or even nine months ago. So yes, your new machine could have an anti-virus database that's quite old.

"If you're a relatively heavy computer and internet user I recommend making sure that your anti-virus database gets checked daily."

There are two things you need to do whenever you install a new anti-virus program:

  1. Immediately update the database. Some installation programs will actually do this for you, but particularly if your anti-virus program was pre-installed, you'll want to make sure, and if needed take this step yourself.

  2. Configure the anti-virus program to automatically check for database updates and download them. That could be once a day when you log on, or in the middle of the night if you leave your machine on overnight. Or you could choose some other schedule. The important thing is that it happen, and that it be automatic - you shouldn't have to think about it after setting it up.

Unfortunately exactly how you do each of those two things will vary a great deal based on exactly which anti-virus program you're running. But do them, you must. Check the documentation for the program you've chosen - this is so important it should be very easy to find.

And for the record, the same is also true of any anti-spyware software you're running. While anti-virus and anti-spyware programs operate differently they do share a common characteristic: they use a database of known malware to look for. In both cases that database must be updated regularly to be able to identify and protect against new threats.

Article C2954 - March 5, 2007 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?


Jan Abey
March 7, 2007 3:50 AM

What is the best&Cheapest way to stop pop ups.

March 9, 2007 7:49 PM

I have tried a few different programs, but for me the best one i have used is the Google toolbar. It intigrates into IE and also has a handy search bar.

February 24, 2008 4:56 AM

company have installed mcafee anti virus(trial version for 30 DAYS). n now how to know whether it is up to date or not, as 1 month is almost over now? plz help me in this.
April 6, 2010 9:58 PM

I installed Avast however it seems its only for email. Don't I have protection when downloading videos from the internet?
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