Originally Posted by cpspecial
I ran into this problem as well when I got my Bionic a few months ago, and RSDed from GB to JB. The phone didn't recognize either the internal storage or the micro SD card. After several reboots, the phone eventually recognized that internal storage existed, and gave me the option to format it; I also was able to press the issue more quickly by installing ES file explorer and attempting to navigate the file system, which brought up the option to format. The stock Motorola file manager did not produce the desired effect.
For the microSD card, I eventually had to (after backing up its contents) delete the partition, resulting in an unformatted card; I booted the phone and manually mounted it (settings--> storage, mount SD card), which then produced a prompt to format the card. An annoying solution, but it did work with two different microSD cards. Even though they worked fine in Windows and in an MP3 player, the phone would only recognize them after deleting the partition and reformatting in the phone.
I hope this is reproducible in your phone, and solves the problem.