The dreaded error 99 on a 20D?

I got the error 99 shooting at a swim meet this past weekend on a Canon 20d. I reset everything(swapped batteries, memory cards, and the lens. Nothing seemed to fix it, the shutter seems to be stuck and wont move while the mirrors keep moving and clapping. Guessing there's no solution for that except the repair shop? Everytime I put the battery in it starts clapping away and wont let me take a pic...and when I slightly twist the lens it'll clap(when it stops sometimes.) I'm sure it didn't get splashed or anything like that...maybe it's a technical malfunction with the shutter. I just switched lens a time or 2, maybe that's the dirty contacts but I also tried cleaning the pins off and that didn't help. Is there such thing as a 'reset' or is my problem most likely just a broken down shutter?
I did break the shutter a while back being dumb and trying to clean it with a vacuum and got it all fixed/most of it replaced. Also I've randomly got the error 99 once in a while but as usual it reset normally. This time the shutter won't move.

You've tried all the basic stuff I would have suggested - a repair shop trip may be the solution. Hope it all works out quick and cheap.

Shutter should fire irregardless of a lens being on the camera or not, if you're looking at it while it's open and nothing's happening while the mirror flips out of the way (try longer exposures to make it more noticeable) then I think it's time for the repair shop.

My 20D had the Err99 twice, and in both cases it was right after I used it in very humid conditions. I couldn't get it to work until a day later, when It started working again with no issues whatsoever.

Leo.

Sounds like the shutter's died. The only thing you haven't mentioned trying is pulling both the main and backup batteries and leaving them out overnight to let the camera reset.