H ichemriof,
Firstly, do you have a SAMPLE MTV video file on your player right now? If you do, then you can check out it's specs to make sure you have the same specification MTV video file.
Secondly, try using this converter from our site here:
MTV Convert Tool 3.06 - MP3 Player Utilities 3.06.
- Try various resolution sizes to see what works on your player.
- Try various video files as well, .AVI as well as WMV to make sure it's not your video files that is the problem.
Also, can you send us the link of where you bought the player from?
Lastly, can you tell me what the FIRMWARE version is of your player as well?
Let us know.