How can anti-virus or anti-spyware software cause problems?
It is important to use anti-virus and anti-spyware software (see Understanding Anti-Virus Software and Recognizing and Avoiding Spyware for more information). But too much or the wrong kind can affect the performance of your computer and the effectiveness of the software itself. Scanning your computer for viruses and spyware uses some of the available memory on your computer. If you have multiple programs trying to scan at the same time, you may limit the amount of resources left to perform your tasks. Essentially, you have created a denial of service against yourself (see Understanding Denial-of-Service Attacks for more information). It is also possible that in the process of scanning for viruses and spyware, anti-virus or anti-spyware software may misinterpret the virus definitions of other programs. Instead of recognizing them as definitions, the software may interpret the definitions as actual malicious code. Not only could this result in false positives for the presence of viruses
