Downgrade blackberry OS

How to Downgrade Your BlackBerry’s Operating System

Step 1 – Uninstall/Install the BlackBerry OS Software
The first step is to delete/uninstall all the versions that you don’t want. On your P.C go to control pannel click on uninstall program or add/remove. Here, you will highlight the OS and then click uninstall. If you aren’t sure which is which, delete all of them and reinstall your preferred OS.

Step 2 – Download/Install the BlackBerry Desktop Manager Software

Step 3 – Backup your data/3rd party apps and then wipe device

Step 4 – Load the Blackberry OS

Now it’s time to start up the Desktop Manager. Select Application Loader and then select ‘Add/Remove Program.’ You need to select all the applications you’d like installed (Blackberry Messenger, Blackberry Attachment Service, etc.).
After that hit Next. On this screen you will get a confirmation of the software/applications being installed. Click next and watch it load the OS

Step 5 -Restore your data from backup (if needed)
After your OS has been loaded, you can now restore your 3rd party apps and back up file. When this process is complete, you’re done! You’ve just downgraded your OS. Give yourself a pat on the back. Keep in mind that RIM and Carriers will only provide technical support for official software releases. So if you want to play around with some of the betas that pop up in the wild, if things go awry the CrackBerry forums are your source for support – if you call into your carrier for help and you’re running a beta, they’ll know it right away and ask you to downgrade to a supported release, which hopefully now thanks to this tutorial you can easily do on your own