How do I wipe the BlackBerry using Jl Cmder? - BlackBerryFAQ
This is an awesome utility to wipe your BB back to factory fresh settings. After it runs successfully you should get the Error 507 on your BlackBerry signifying there is no OS installed. Then you can run Desktop Manager and put the latest/greatest OS onto your Bold. Be advised, sometimes it is necessary to run JL_Commander multiple times to get it to wipe your device. I had to run it like 20 times once, but it's easy and fast. Just a couple of mouse clicks and a couple of seconds.