I have a mmp8567 and

My MMP8567 screen read ''boot error shutting down''.

Update the firmware. Download directly from Memorex site, Support section.

Everytime I plugged it in to the computer the computer would find it but then it would disappear almost immediately.
I downloaded the Updater program from Memorex but it couldn't find the player.
The directions from Memorex said ''Hold down the play button and plug in usb cable.'' Another set of Memorex directions said, ''Hold down the power button and plug in usb cable.'' Neither worked for me.

SOLUTION: I finally held down the LOCK/UNLOCK button and plugged in the usb cable. My computer found the player immediately and a software driver window popped up asking for a driver. I let windows search the internet and it found and installed the driver. The driver it was looking for was: ''player recover device class driver''

After windows confirmed it recognized my mp3 player I started up the Firmware update program and was able to update the player.

I tried to be clear and detailed. Good Luck ;-)