Have you forgotten the password to your old account? You're going to need another email address to recover your old account. One that isn't currently linked to an Xbox live gamer tag.
Follow the instruction on the next link titled "What to do if you can’t use any of the password reset options"
It will take you to a page
https://account.live.com/acsr which enables you to enter a new email address for contact. To recover your account you will need ad much information as possible as per the first link,
Tips for completing the online account recovery form
Provide an alternate email address – make sure you have access to this email address so that we can send your account information to you.
Answer as many questions as you can.
Use the information you provided when you created the account or last updated it.
Submit the form from a computer you frequently use.
Keep in mind that your email address may be country-specific. For example, if you created your account in Sweden, your domain would be “hotmail.co.se” instead of “hotmail.com.”
Hope this helps.
Did this solve your problem?
Sorry this didn't help.
Great! Thanks for marking this as the answer.
How satisfied are you with this reply?
Thanks for your feedback, it helps us improve the site.