Change Your Sign-In Account on Your Surface
You may want to change the account you use to sign in on your Surface. For example, you may want to sign on with the same account you use for your Xbox, or you may want to switch to a newly remembered Microsoft account.
The simplest solution is to create a new User Account for your new Microsoft account by following these steps:
Open the Settings charm, and then tap Change PC settings.
Tap Add a User.
Type in the e-mail address associated with your newly remembered Windows Live ID (or the e-mail address associated with your Xbox gamer tag).
Log back on to your old account and then move all of your data to your Surface’s Public folders.
Double-click a library — Music, for example — and you see both the My Music folder and the Public library, where you should now copy all of your music.
Finally, log onto your new account and copy your files from the Public folders back into your own folders. When you’re through, you can log off your old account and log onto your new account.
After a few days, feel free to delete your old account, when you’re sure you no longer need it. (Make sure you’ve elevated your new account to Administrator, so you’re able to delete the old account.)
Deleting your old account also deletes anything you’ve purchased with it, including apps, movies, songs, and other items.