MP4 4GB problem with firmware

I bought MP4 4GB and I had a problem: when I stored some folders in MP4 and I wanted to remove them I couldn’t. I tried change my firmware but I think I chose bed firmware and I’m looking for:

MP3 Player
LSD_9301_10
2006-11-21
9.0.48
2005-01-09

Please help me what I have to do! My mail:

mac2010@wp.pl

it should be in the menu

mac2010,
Sounds like you have a hacked player. This is very common for the China players of 4GB in size and larger. See
http://reviews.ebay.com/THE-OFFICIAL-4GB-MP4-PLAYER-SCANDAL-ON-eBAY_W0QQugidZ10000000002547758 and http://www.mympxplayer.org/my-fake-4gb-mp3-player-detailed-findings-vt424.html

The firmware was not the problem and updating it was a bad decision. The 9.0.48 firmware can not be extracted or backed up at this time since no tool exists now to do that. Changing firmware on any of these players is very risky. There are hundreds of different firmware versions. I have the exact same version as you, but I can not extract it to give it to you.

If you can still get the player to start up, you can remove the memory hack http://www.mympxplayer.org/how-to-removing-memory-hack-vt2400.html
and things should be fine, but your 4GB of memory is actually much less because you never had 4GB.

If the firmware has been made non-working, just wait. Someday there should be tools to extract the firmware and you will be able to put the right firmware back in.

Hello I Need help with my mp3/mp4 player. there is music on it but when i try and play it, it says format error.

what do i do??? is there something wrong with the firmware??

the firmware version is:
QS91B11
FGD177FLW-7735B
2007-08-07
9.1.52
2005-01-09

please email me on deleadeyele@hotmail.co.uk if you have any solutions.

thanks