[c#] ProcessStartInfo hanging on "WaitForExit"? Why?

Mark Byers' answer is excellent, but I would just add the following:

The OutputDataReceived and ErrorDataReceived delegates need to be removed before the outputWaitHandle and errorWaitHandle get disposed. If the process continues to output data after the timeout has been exceeded and then terminates, the outputWaitHandle and errorWaitHandle variables will be accessed after being disposed.

(FYI I had to add this caveat as an answer as I couldn't comment on his post.)