When someone checks the option to shut down the PC after defragmenting a drive, any dialog claiming that the drive could not be fully degragmented should be supressed to allow the machine to shut down.
That is, the priority should be to handle the shutdown request; not to stay up to report a rather trivial message while actually preventing a shutdown. Either that, or report any trivia as a part of the countdown dialog to shutdown.
Other than this minor issue, you have a very nice program. Thanks for writing it.
while I agree with that, what about those people who run DF like you do, at shutdown, and they do that for ages - months and months - all the while DF has been telling them "Hey I can't complete for some reason, there was a problem" only to have that dialog window disappear when the PC turns off.
they would never know until they did a DF and waited for it to finish.
so either action has downsides. maybe something along the lines of when DF is run again, if the previous run didn't finish normally, it would pop-up some sort of message.