| | 04-23-2013, 10:56 AM #172
Connect your phone to your computer with a cable, then back up your pictures, music, and videos.
In the App list, tap Settings Settings icon > About.
Tap Reset your phone.
When the warning message appears, make sure you're really ready, then tap Yes. Your phone will restore itself to factory settings.
When your phone restarts, your phone will guide you through several steps to set up your phone. When you get to the Sign in with a Microsoft account page, sign in with the new account you want to use.
After that restart your phone!!!