Change Your Sign-In Account on Your Surface
You may want to change the account you use to log in on your Surface. For example, you may want to log in 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 the Accounts category, tap Other Accounts from the Accounts pane, and then tap the plus sign icon next to Add an Account.
Type 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 in to your old account and then move all of your data to your new account.
You can do this with either OneDrive, a flash drive, or a portable hard drive. Copy the contents of your Documents, Music, Videos, and Pictures folders.
Log into your new account and copy your old files back into your new folders.
When you’re through, you can log out of your old account and log into 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 through the Microsoft Store, including apps, movies, songs, and other items.