I have a BB 8120 with T-Mo. I upgraded the OS to 4.5.0.124 as explained in one of the threads at the top of this forum. I am experiencing some issues with some apps. Applications such as: Viigo, Google Maps, JiveTalk, and Slacker won't run on my device. Is it because I don't have the right service book for installing an OS version that wasn't built for my carrier. Is there something I can do to fix these? Thanks!

try to delete and reload the applications again.

I've done that, it still doesn't work. :(