How I got my Chinese MP3 MP4 Player to play video.
 

This nearly drove me crazy, so when I finally solved it I thought I'd share, so others might find this information more easily.
Today I found a recent thread where someone else had solved this problem, but their instructions on how they did it are no longer available.

This was an eBay purchase from China.
Title said "16GB 2.8" Touch Screen MP3 MP4 VIDEO PLAYER 3.0M Camera"

The instructions said it would only play AMV format videos. Believing that was my first mistake.Lots of wasted time downloading and trying AMV converters.I was suspicious this was wrong, as it came with a sample video which was AVI format.

By playing the sample I was able to see that the video codec was Xvid, resolution 320 x 240, frame rate: 22, and the audio was MPGA, sample rate: 44100hz, Bitrate: 128kb/s.

From this I went looking for an AVI video converter which had those specs as an output format option. Hours and hours lost looking for a converter which would do that. I tried MP3_Player_Utilities_5.09 from here with no success. It includes AVIconverter, but the 320x240 resolution wasn't available, and probably some other part of the output stopped it from working with my player.
By accident I found a later version of AVI Converter, and this was the answer, AVI Converter 3.0 .
The setup file is called "AVIConverter QVGA 20f En Setup"
Various comments about it here
Google
The one I got came in a collection called "MP504_driv_2k_xp32_vista32" from driverscollection.com, and was associated with a Sweex player.
It's here DriversCollection.com
I was only able to find the download link again now because it was still in my Firefox downloads list.

This is a bit of a scroller I know, but I wanted to list all of the clues which finally got me to the solution.
Hopefully the search engines will index these, so people are brought here if they look for the same things I did.

I now suspect the memory size of the MP3 MP4 player is a hack/fake. At least I can load it with videos to see how much it will hold.

Some photos of the player are attached. It's very similar to a Manysung YX-2827 from Creative Universe Technology Limited.

.
I see my link to the driverscollection page doesn't work anymore.
Another file that has the correct converter is called MP502_MP504_driv_2k_xp32_vista32.zip

You can get it from the Sweex site, their Black Onyx player uses it.
Link>>Black Onyx MP4 Player 4 GB Sennheiser Touchbutton - MP504FM
.

Informative post! Would like to try it out, but my player has bricked. Same model as yours actually.

How did your player get bricked?
I've thought of resetting mine to show the actual memory (it's been hacked) but wasn't sure in case I totally wrecked it.

I managed to format it in Windows, now it just wont boot. Working on a solution though!

Hope the plan works.

Yep, I got suckered into one of these on Ebay,... couple of sellers on there at the mo,.. seems to only have 1.7 Gb memory,...
I cant get a formatter to run a true memory status on it,... the MP3 Utilities tool wont run on my laptop,.. anyone point me to a formatter??

Cheers, Fred

See the HowTo section of the forums. I've started a thread about the hacked memory.

In addition to hacked memory, my wife's player came with ear buds, USB cable, and audio/video cable. The ear buds didn't work. Sound only came out of one side and the player sound wouldn't cut out when they were plugged in. Another set of headphones worked fine. The USB cable also didn't work. The computer recognized a device was plugged in, but showed up as an unrecognised device. Another USB cord (from my Garmin GPS) worked fine. Sheesh.

Mine had a faulty USB cable too. I thought the player was faulty as it wouldn't charge the battery.
Not sure why I tried a different cable, but I'm pleased I did.

You mentioned instructions. My wife's purchase didn't include instructions. I have the basics figured out. Enough for her to use it. The one button I can't seem to get to function at all is the camera button. She can take snapshots by tapping the camera icon on the screen, but I expect that the camera button should also take photos.