Originally Posted by WTO
Thanks for your guide. So do you mean that if the data are encrypted, they will only be recognised by that specific device that encrypt them? What if someone took it out (from my device) and insert it to their BB device, can they have access to my data?
Yes, basically correct. Only viewable on that device with an exception noted below.
Go to Options > Media Card
The second setting down is "Encryption Mode". You can choose Device, Security Password, Security Password & Device. This will encrypt the files like spreadsheets and docs.
Now the exception. If you use "Security Password", you can move the card to another phone and view the files if your device password is set the same. This matters if you had to warranty exchange the phone. If you use "Device" I think you lose the files forever if the device dies.