hi! i dont speak very well english! but i will try, because i cant find solution to my problem :(... well... mi sister have a bb 8100, and i uptade the operative system to 4.5... everything works! but, when i try to enter in the pictures and music, the BB is restarted, over and over again... i dont know if is the microsd, because when i extracted it, the cellular works exelent!! but i enter the memory in a camera, and work... i dont know what to do... I format the memory and nothing... i have the BB whitout the memory, the only way to work... thaks... and sorry for my english :D