I cannot view any of my media files (pictures, music etc.) on my Blackberry Torch. However, I can view them all normally on my PC. Only the files saved to the device memory itself and not the memory card can be viewed on the phone.
There might be two possible scenarios.Either,your phone is unable to read the formats present in the memory or the memory card is not being detected by your phone.
In such case,try backing up the files from the card and then format it by using your phone and not PC.Then transfer all the files back to memory card and check whether it works or not.
are they encrypted in memory card?