Before you start the process you will need your Blackberry phone, a USB cable to connect it to your PC and the CD that came with your phone.
Step 1 : Install the RIM BlackBerry Desktop Manager from the CD provided with your phone or download it's newest version from here. Select your phone on the page and download the appropriate software. Currently it is at version 4.7.
Step 2 : Start up the BlackBerry Desktop Manager by opening it from Start -> Programs -> Blackberry -> Desktop Manager or its Desktop shortcut.
Step 3 : Now connect your Blackberry phone using the USB cable to your PC. It may take some time for your phone to get detected. If the phone is successfully connected, you will see a Connected message on the main screen of the Blackberry Desktop Manager in the status bar.
Step 4 : From the main screen of the Blackberry Desktop Manager, select the Backup and Restore icon .
Step 5 ; Now you can choose what types of data you would like to include in the Backup file. From the Backup and Restore home screen, select the Advanced option. Now the Blackberry Desktop Manager will scan your phone and fill up the Device Database tab.
Step 6 : You will now see a screen containing two columns, one on the left side for the Computer Database and another on the right side for the Device Database. You can now select what items will be included in the Computer Database, which is nothing but your Backup file. Use the arrow button to move the data records to the Computer Database column.
Step 7 : Now Select the File option on the same screen and give a name for your Backup file. Select a location and save this file in some safe place.