i was tyribng to upgrade my OS to the newest leaked one
with the " Loader " after i click it and it goes into the steps
when it gets into the step where the phone Has to restart " rigth after the backing up step "
the phone get stuck on the " Black blackberry loading screen "
and an error message appears sayng the USB error smth !!
That happened to me once. I was really panicing as well. What I did was pull the battery. Put it back and restart the phone. Nothing was wrong with it. Then I re-started the upgrading process. Not sure if that was the right way, but it worked for me.
Posted from my CrackBerry at wapforums.crackberry.com
I use BBSAK to load new OSs and have never had a problem. I loaded .448 without a hitch recently, and then .450. Use BBSAK to 'wipe' the phone, and then load the OS. There are many threads here to guide you. Do remember to do a back up before you wipe your BB though.