Help Sorry this video cannot be played

[SeKour]

I've read various postings of people who are attempting to play transferred videos - that are formatted as .mp4 by the way (the native video extension for the android OS) - but are receiving the same message I am: "Sorry, this video cannot be played." It seems that everyone wants to say it's an issue with DRM... but that's an excuse.... The video I've transferred is a home video with no encryption; simply .mp4 format.
Can someone help me with this, because I'm quickly becoming a "non-fan" of Android.