I upgraded my OS 4 yesterday to OS 5 on my BlackBerry Curve 8520 and I got most of my apps. They work perfectly. FaceBook, Tumblr, Twitter, Windows Live Messenger, AOL Instant Messenger, Yahoo! Messenger, Google Talk and MySpace all work. Then I tried downloading BBM and it says that it's installed and everything but it's nowhere to be found on my phone. I checked all my folders but it's not there. The same thing happened with BlackBerry AppWorld. Says it's installed but I can't find it either. It's not visible on the phone and I don't know why. Someone please help me. I've been working non stop trying to figure it out since 6pm yesterday. I resent my service books so that's not the problem.