how to go back unroot status by reinstalling ROM of Milestone 2

http://forum.xda-developers.com/showthread.php?t=998624&highlight=nandroid+open+recovery

Ok theres a bug with RSD Lite 4.9.. download your SBF of: http://and-developers.com/sbf:milestone2

Put the .sbf file (You have to unpack the .tar file) into C:/

Shut down your telephone, hold ArrowUP(On the phone) AND PowerButton(On the phone aswell) hold it for like ... 10seconds, then stop. the "Bootloader" screen should appear (Black screen with white font)

If you got that, plugin the USB Cable.

Then open the windows command promt
and type:

Code:

 cd C:\Program Files\Motorola\RSDlite\ SDL.exe -f [FILENAME].sbf -t 2

Note: Replace "C:\Program Files\Motorola\RSDlite\" with your InstallDIR
and [FILENAME] with the SBF Name (You can rename it to something smaller like: UKSBF.sbf)
Then RSD lite should start .. and flash your phone.. if it doesnt start and shows the 000710something error just try pressing "START" wich should appear after the error..+

PS: Next time use z4root it has a UNroot function