I am writing an application that stores the movies in the photo roll into the local documents folder for the app. I can play remote movies using the MPMoviePlayer, however trying to play a movie stored in the documents folder for the app always returns MPMovieLoadStateUnknown.
The notifications are all getting sent and received from the default notification center (MPMoviePlayerLoadStateDidChangeNotification, MPMoviePlayerPlaybackDidFinishNotification).
An alert box shows up shortly after getting the loadStateUnknown message in the console, saying that the movie could not be played and the app then receives the movie playback completed notification.
I think that it may be a case that the filename (MPMoviePlayer can only take a URL as the asset location) cannot be found. Has anyone dealt with this issue or similar?
Given that none of the other answers seem to resolve the problem, I'm inclined to think that the problem might be with the Documents file path you are producing.
You should be using the following method to generate the path to the application's documents folder:
NSString *userDocumentsPath = nil;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
if ([paths count] > 0)
{
userDocumentsPath = [paths objectAtIndex:0];
}