Hello,
I think that you have same mpx player as me.
(
http://www.mympxplayer.com/album_showpage.php?pic_id=24 )
If it is so - you will need to :
- open mpx player, shortcuts pins on chip to put player in revovery mode,
- then using upgrade firmw. tool upgrade it with basic FULL
firmw.(like MP-683E-GC-V01 - this is version 3.0.4.2).
Your mpx player will work now just like some usb memory stick, and
screen on mpx player will NOT work yet - don`t worry, that`s normal.
- restart mpx player, and now you can upgrade your mpx player
with orginal (backuped) firmware. After restart, all should be ok - as new.
If you are unable to do this (last step) - you have option to try 2 other firmw. files wich are ver. 3.2.16, not like orginal 3.5.35.
hope this helps you