The same for me, like jcorkin.
I've Selected Update SD Format from Wince Upgrade then went to testmode and Opened My Device and copy the contents of the "Storage Card/SD Card" to the root of "My Flash Disk" in the unit, here is the PROBLEM, unit says no enough room, so i deleted the complete content of "My Flash Disk" in the unit to have room but it still asking me for moer room, so i can´t complete an of course my X910 does't start.
So please , some help!!!
TX.