Comment 10 for bug 879496

I was having this issue and found a workaround for my particular situation - I disabled the UPnP option and configured my router manually to forward the port, then disabled desktop sharing, then enabled it again (it did not work if I simply unchecked the box - the restart was required). I went back and tried several configurations after figuring this out, and it seemed to be the only variable that mattered for me. I had also tried a variety of solutions suggested in forums with no success.