If you bit off more than you can chew, here's how you go back to stable software.
by
Andrew Cunningham - Feb 13 2015
"Luckily, it's not hard to roll your phone back to Windows Phone 8.1, at least as long as you have access to a PC and an Internet connection. Download the Windows Phone Recovery Tool (
EXE download), install it, and launch it. Connect your phone to your PC, and the app should automatically detect it. Though it won't detect any newer software for your phone, click "reinstall software" and the app will download and reinstall Windows Phone 8.1 for you.
The one caveat about the downgrade process is that, unlike the upgrade process, it doesn't preserve any of your data. If you have photos or other files on your phone that you'd like to keep, offload them to your computer or to an SD card that you remove from the phone before you downgrade. You'll need to get your phone set back up the way you want it afterward, but at this point that may be preferable to running early beta software."
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