1. Go to live.xbox.com/Account/BillingAccountInformation.
2. If required, type in the e-mail address and password associated with your Windows Live ID, and Sign in.
3. Under Country/Region you'll find your Gamertag's current region.

Redeem prepaid codes on Xbox.com

1. Go to live.xbox.com/RedeemToken.
2. If required, type in the e-mail address and password associated with your Windows Live ID, and Sign in.
3. Enter your 25-character prepaid code, and click Redeem Code.

Redeem prepaid codes on your Xbox 360 console

1. Turn on your Xbox 360 console, and then press the Guide button on your controller.
2. Select Marketplace, and then select Redeem Code.
3. Enter your 25-character prepaid code.
4. Confirm the item.

For more information, please visit support.xbox.com.