In general, a log file will tell us much more than a screenshot:
Problem? Make sure to post a log and/or crash dump -- HOWTO
But to your problem, did you record in mp4 or flv format? If the mp4 file did not close properly, it would render useless, thats why we generally recommend to record in flv, and copy to mp4 if necessary later.
If you have media-info at hand, you could read out the info of your saved files and see if the header is complete.