Also, if you're going to downgrade, make sure you read the instructions for that from the 101:
If you're installing an operating system that's older than your current software, you'll want to download the OS to your PC and launch the .exe file to install the desired OS to your PC.* But when you plug your device into your PC after opening the Desktop Manager, the app won't find any updates and you'll have to instigate the install process yourself. To do so, click the Application Loader icon on the Desktop Manager home screen and then click the Start box on the right side of the screen, beneath Update Applications. The software will then search for updates and won't be able to find any.* On the following screen, click the Advanced tab under Device Application Selection, make sure the list of applications on the next screen includes all programs you wish to include in the install and hit Next again. Choose to backup your application data on the following screen and hit Finish to begin the install
Good Luck!
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