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Anti-virus updates (from well written anti-malware tools) should not be accumulating virus definitions on your hard drive.

I searched, but I couldn't find any other question of this nature. It affects anti-virus software, free or requiring a fee after a certain period.

The problem is having to update the security definitions which are up in the megabytes. I have to run my computer on a daily basis or else if allowed to accumulate, this will take lots of time to install them. Every day about 3 to 4 megabytes must be installed. The question is don't these updates keep using disk space? I'm running out of space trying to keep up with them. Isn't this true? Thanks for anything you say.

In this excerpt from Answercast #14, I talk about reputable anti-virus software updates and the space it should be taking up on your machine

Space for virus definitions

In general, (since you haven't mentioned what software you're running), the updates that you get replace (they do not augment, but they replace) the updates from the previous day or from the previous accumulation of updates.

So what that means is that no, they shouldn't be taking significantly more space.

Well written anti-malware tools

I say that as a general rule of thumb.

Of course, anti-virus programs (specific anti-virus programs) can certainly be written not to behave this way. They could certainly be accumulating lots and lots of updates in an inefficient way.

My experience with most of the reputable tools, (most of the tools that I recommend) is that the updates they download do not keep adding up forever. They do a way that minimizes the incremental amount of space they take up to be only enough for the updates that are truly new; the information that is truly new.

If you're downloading three to four megabytes every day, my guess is you've probably got three to four megabytes of updates on that machine. You'll not have three one day and six the next, nine the next. You'll have a set of updates that takes somewhere around three to four megabytes.

Where is my disk space going?

Where your disk space is going is potentially a different question.

I would point you at a couple of articles on my site:"Where is my disk space going" being one of them. That will help you identify what's eating the disk space on your hard drive.

I strongly suspect (unless you have a very poorly written anti-malware tool) it is not because of an accumulation of anti-malware tool updates.

End of Answercast #14 Back to - Audio Segment

Article C5294 - May 3, 2012 « »

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.

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1 Comment

Mary Palmer
May 5, 2012 6:31 AM

Whenever I open my Pictures I get all these images I did not put in. There is a bunch!!!
What can I do To stop this??
Sincerely,Mary Palmer

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