These files are from Motorola's Development site and I take no liability with anything that happens with your device if something goes wrong.
DO NOT ATTEMPT TO FLASH THIS FILE ON ANYTHING BUT THE VERIZON WIRELESS MOTOROLA XOOM Z600 (3G MODEL) OR YOU WILL HAVE A SHINEY PAPER WEIGHT!!!!
You're going to need to have the Android SDK installed. You can download it here:
ANDROID SDK - DOWNLOAD
XOOM Firmware Downloads:
Unzip the files in MZ600_HRI66.zip and move or copy them to the /platform-tools folder in your SDK folder.
Connect your Xoom to your computer. Type:
adb reboot bootloader
Wait for it to reboot into the bootloader.
Type the following commands, waiting for each to finish before continuing:
fastboot flash boot boot.img fastboot flash system system.img fastboot flash recovery recovery.img fastboot flash userdata userdata.img fastboot erase cache
You've now successfully flashed your Xoom back to stock. Now it's time to relock the device. Type
fastboot oem lock
wait for the menu
then press the volume-down button.
Then press the volume up button.
It'll take a minute or so, then reboot. You're now completely back to stock and ready for the update.