There are several sub folders in my C:\WINDOWS\TEMP folder named plugtmp
with numbers after them.. For example:plugtmp-1, plugtmp-2. These
folders all seem to be empty. I gather that they have something to do
with Mozilla, but what are they and can they be safely removed?
As long as Firefox isn't running you can delete most of the temp files
without worry, but I would recommend using a program to do that for you.
A good, customizable program for just that reason is CCleaner. It's free
as in beer and it has no spyware, malware or other harmful hidden
software to speak of. Also, it's updated quite frequently.