If it's an upgrade to what you have all you need to do is install the new OS to your PC then run Desktop Manager with the BB connected. The Application Loader will wipe the device after making a backup. If the OS version didn't come from the carrier that is branded to the BB you will need to delete the vendor.xml file located in c:\program files\common files\research in motion\apploader after installing OS to the PC and before running DM. Hope this helps...

Here is a link with instructions for wiping the device manually before loading the OS. See post #2 in this thread.

http://www.blackberryforums.com/gene...highlight=wipe