v0.48.64 (however this bug affects all previous versions too I think)
x2.3bPro w/ 4981.06
When sending files to Xbox with FlashFXP (haven't tried other clients), after a lot of error 426 Couldn't open file for writing, error#123 consecutively* (because the files being sent had illegal filenames), when a valid filename is given and a transfer should begin, Avalaunch locks up and has to be rebooted.
It may be an issue with the number of #123s within a certain time-period, or the number of #123s total, I haven't tested it. I know that in order to reproduce you have to get more than 2-3 #123s.
* for example, like 20 times in ~5 seconds