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2. Do a backup of your device first, using Desktop Manager > Backup. Close Desktop Manager upon completion and unplug BlackBerry. Get DM here http://us.blackberry.com/apps-software/desktop/
3. Download the OS file to the PC then install it to the PC by running (double clicking) the file you downloaded.
4. Go to c:\program files\common files\research in motion\apploader and delete the file named "vendor.xml."
5. This step is not needed unless there is an issue on next steps. Use BBSAK from BBSAK.org and wipe the device (after doing a complete backup) then after you get the error 507 (no OS installed) then proceed to step 6
6. remove internet connection to PC and reboot PC.
7. Plug in BlackBerry and double click on "Loader.exe." It's located in the same place as the above vendor.xml file was in.
