There may be some information in the link below that will help you get it working again. You might try looking at the information on fixing a bricked BB.
I charge my BB for 5 hrs and I got a screen 507 error.
But, When I tried to install the OS, the device is rapidly disconnecting from the PC, even if I remove battery.
I tried a lot of posts here but didt find a suitable method....Can anyone please help me ?
You are going. to haf to realize that djm1947 is right . And that your BB is nuked aka bricked. And follow
The steps on how to restore a nuked BB. Good luck.
Posted from my CrackBerry at wapforums.crackberry.com