Are there any viruses that cause the hard disk space in one's computer to increase or decrease by a few MB after some time? (I hope you can answer this question, as I believe that this is a virus, but a virus scan revealed nothing.)
Yes, there are numerous viruses that could in fact increase or decrease the hard drive storage. Some viruses add data to files, while others destroy.
I recommend you get a current virus scanner, then look for special virus software for your OS or applications.
For more information on this topic, visit these other SearchSecurity.com resources:
Virus Prevention Tip: Cleaning out a virus infection
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