Thanks a lot to Franz ,
the firmware he sent to me saved my mp4 player
mp4 is a glacier alike one. it has 2" display and CTW500 chip. firmware version is 9.0.50 , ACT2097_75 .
computer detects it as an ADFU device, I used mp3 utilites 4.0.9, clicked recover button, selected firmware. The problem is to understanding chinese
, guessing language setting options, you have to find english
