This will require you to have BlackBerry Desktop software installed on your computer.

Please see the link below for the software download:

1. Click on Device from the upper left-hand corner of the BlackBerry Desktop Software  and selectBack up from the drop-down list, or simply click Back Up Now from the  main screen of the BlackBerry Desktop Software. 

2. Mark the appropriate customization level (Full, Quick, Custom). In most cases,  select Full. 

3. Input a file name if desired, or leave the default text.

4. Leave the Encrypt backup file unchecked.

5. Select Backup.