Somehow in my quest to add AOL to available "mailto" programs (which I belatedly found out how to do via an add-on), I think what I did was inadvertently create a bogus https address that shows up on the File>Email Link selection as file "IOSX6AAU," which I can not find anywhere in a search on my computer. When I click it, I am asked what application I want to use to open it. I've tried several hours of Help topics around setting or changing default programs, and it doesn't show up at all under Firefox menu's Options>Applications>mailto display. It doesn't affect the operation of my computer, but it is an annoying detail for which I have taken up an annoying quest to correct. If someone knows the answer to this riddle--and also, out of curiosity, how I managed to create this situation--I would be grateful to learn it.