In order to hard reset a BlackBerry 9720, you should perform the following steps.

Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
BlackBerry 9720 device will be brought back to the default configuration of a brand new device.


1. For starters, turn on your phone by pressing and holding the Power button.


2. Open the application tray and go from Options to  Security, Security Wipe.

3. Now go to the text box and tap in the word "blackberry".

4. Choose the Wipe option.

5. Done.