Random Search files-programs on A drive

I know there is a way to eliminate the random searches on my “a” drive when working on the computer, I just cannot remember where to fix this from happening. I am running Windows XP Home edition.
It happens at unexpected times when working on my PC. It is not virus related, I have all updates as recent as two days ago.

This happened once before and I was able to modify a setting somewhere but cannot remember where it was…

Thanks
Chuck