On more than one occasion, I found that playing back a streaming video from a server at home resulted in the "Cannot play video / File is damaged or incomplete" error. That didn't make sense since the videos played fine elsewhere.
The culprit? Commas in the filename. I'm not sure if this has been posted before but I'll put it up anyway.
I removed the commas from the affected videos and voila. Playback works.
Hope this helps anyone with the same problems. Post back with your results.
