Can't find drive F ???

Ok when I try to install or uninstall a program I will get a erro that states something of the like of "Invalid drive F" or "Cant locate drive F" (sorry dont know exact wording have nothing I want to install or uninstall currently)
I don't have a drive F, the only time I had a drive listed as F was when i had a external drive labled "G" and while it was connected had a thumb drive inserted into a USB port, I was transfering some files so the thumb drive became "F".
Now the issue is whenever I try to install or uninstall any program I must plug the thumbdrive in to prevent the "Cant find F error". This is a major issue becasue I dont always have the drive with me
Is there anyway that I can keep this from happening? a hidden setting or something or will I now have to always have a thumb drive handy to pop into the USB port in order to prevent this error?
I don't have a drive F, the only time I had a drive listed as F was when i had a external drive labled "G" and while it was connected had a thumb drive inserted into a USB port, I was transfering some files so the thumb drive became "F".
Now the issue is whenever I try to install or uninstall any program I must plug the thumbdrive in to prevent the "Cant find F error". This is a major issue becasue I dont always have the drive with me

Is there anyway that I can keep this from happening? a hidden setting or something or will I now have to always have a thumb drive handy to pop into the USB port in order to prevent this error?