This afternoon, Recovery mode worked (Hold Switch On, REC + Power) and I copied the latest firmware to it. After unmounting the drive, I disconnected it from the USB cable. To my astonishment, the same results occurred: still rebooting.
It was time to search Google. Everything pointed to the firmware. Someone even suggested loading the firmware 3 times to see if it would take. It was almost time to give up when I found a small post suggesting dropping a blank file called sansa.fmt onto the recovery partition. After an unmount, the Sansa Recovery Mode formatted the drive and it booted normally, minus all the content, of course. At least I didn’t loose the device!
What firmware image did you use? I’ve been trying pp5022.mi4 with and without that sansa.fmt file but no luck, I always get “Load main image failed Switch to Recovery mode’
Never mind, my device is actually a e200 ver 1. I used the correct boot rom and mi4 file for that version and it works fine now.