Thanks. Perhaps I'll just avoid that outlet. I had another outlet about 4 feet away that only had 1 wire with black, white, ground that I have already converted to GFCI. I was just hoping to be able to convert and use both but maybe I'll just act like this one doesn't exist unless somebody else chimes in with a solution. I have no clue how to track down where the wire may go, everything around it, the floors above and below are finished and I checked a couple other outlets in the room and none of those have contained red. And the only switches currently in this room control the ceiling fan and light separately. I kind of suspect at one point it was switched as the notes on the breaker box for the entire house are very detailed and seem to indicate that several outlets throughout the house are switched but since we purchased the house there isn't a single outlet we've found that actually is switched. All switches are accounted for with ceiling lights and fans and all outlets (unless there's one we've not used in the 4 years) have always been on.