About the device password
If you set a BlackBerry® device password, you'll be prompted to enter your password to unlock your device.
If you forget your password, it can't be recovered. If you exceed the number of allowed password attempts, your device deletes all your device data for security reasons and you'll be prompted to set a new password. If your device uses a BlackBerry® Enterprise Server, depending on the IT policies that have been set by your administrator, data on your media card might be deleted as well. For more information, contact your administrator.
Research In Motion recommends that you regularly create and save a backup file on your computer, especially before you update any software. Maintaining an up-to-date backup file on your computer might allow you to recover device data if your device is lost, stolen, or corrupted by an unforeseen issue.