You need to be in RockUSB mode first to flash the firmware, you can still work with a white screen.
Double click on the remove hardware icon in your system tray.
If you are in RockUSB mode you will see the icon in the window like this:-
To get into RockUSb mode
1) switch the player off, using the proper on/off switch
2) hold down the menu button (try other buttons in turn if menu button don't work).
3) connect the USB cable from the PC
4) wait for a full 10 seconds with the button held down
5) look for the RockUSB icon.
6) then release the button
7) If you see the RockUSB icon, load the firmware for your player using Consumerupdate program.
btw, if you want to try and match the EXACT firmware you need the serial number off the printed circuit board, mine was "ESR013-YD093_A_V2" for example, and type the first part e.g. "ESR013" into this search engine http://en.s1mp3.net/