How to: How to encrypt internal and external file systems on BlackBerry smartphones
Important Part: You can connect the BlackBerry smartphone to the computer to transfer files between the BlackBerry smartphone and the computer, or use Bluetooth® technology to send media files to or receive media files from a Bluetooth enabled device.
Turning on the mass storage mode option on the BlackBerry smartphone allows you to transfer files quickly over a USB connection between the media card and the computer without using the media manager tool of the BlackBerry® Desktop Manager. When you transfer files to the media card using mass storage mode, the device does not encrypt the transferred files using mass storage mode even if the BlackBerry smartphone is set to encrypt files stored on the media card. If you transfer encrypted files from the media card using mass storage mode, the computer cannot decrypt the transferred files using mass storage mode.