Options -> Security -> Encryption.
You can enable Media Card encryption but be careful as it cause you more headaches as the encryption is either tied to the device or the password. So you can easily lock your self out.
Make sure you keep a backup for just in case purpose.
Encrypting Media files can also interfere with your camera, video recording, and voice recorder apps. So if you start to see issues with any of those disable the encryption and see if it fixes your issues.
8830 -> 8330 -> 9550 -> 9650
Just think about how far BlackBerries have come from then till now... And what else is coming.
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