I upgraded my Blackberry 9300 v.5 to a v.6. It went well, it was able to boot after the upgrade but it was far too slow so I decided to reboot it by taking out the battery, it opened, it showed the Blackberry logo and it was loading but after it has finished loading, it won't proceed to the home screen so I waited and after a few hours my screen says "app error 603" or something like that. I tried taking it to a technician and they said they would have to re-program but it costs a lot, so I'm wondering if anyone can help me with this ASAP. Thanks