MP4 files won't play on nokia when I send them from the pc

So,I have a nokia n97,and I tried to send a mp4 via bluetooth/usb cable/uploading on card.
After I detected it on my phone,the icon was like the one on a music(audio) file,and it was opened with the music player.After a few seconds,the seconds didn't appear,they were listed as --/--,and after a few more seconds,it said unable to play,file corrupted.
Any suggestions?
Thanks in advance.

Are the MP4's subject to DRM protection? It might explain things.

There are, to the best of my belief, programs which circumvent DRM protection... however since it could be construed as falling outside the rules of the forum to discuss that I can't really say any more...

In my part of the world it's considered legal to back up original copyright material, however I can't comment on how that might apply elsewhere of course.

It's also possible your phone lacks a necessary CODEC or that there are errors on the memory card of course.

I have no idea what DRM is,the phone runs mp4s downloaded directly on the phone smoothly,so the codec shouldn't be the problem,and the mp4s work on the pc.

DRM is Digital Rights Management, I would normally include a Wiki link, but it's pointless today...

BBC NEWS | Technology | Q&A: What is DRM?

^
Gotta love sopa and pipa...
Anyway,any suggestions?

Take the time to Google something called Tunebite...

^
Thanks,I'll see what's up with that.