Format your media card or built-in media storage
Depending on your BlackBerry smartphone model, you might not be able to format your smartphone's built-in media storage.
If you format your media card or built-in media storage, all of the data that's saved to your media card or built-in media storage is deleted. Research In Motion recommends that you regularly create and save a backup file on your computer, especially before you update any software. Maintaining a current backup file on your computer might allow you to recover smartphone data if your smartphone is lost, stolen, or corrupted by an unforeseen issue.
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