How-To: Secure a Gamertag

Step 1: Changing your password

Once you've logged into the account you wish to secure, click this and change your password, then click next once you are done.

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Step 2: Changing security proofs

Firstly, go to this link and then add as many pieces of recovery information as you would like. What you put on here will be used if you ever need to reset your password and to verify login attempts. Once you've added your information remove all the old security info. You will also need 4 digit codes to verify the email/phone number you are putting on the account, so make sure you have those ready.

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Step 3: Alias change & removal

An alias is what you use to sign into your Microsoft & Xbox account. Go here and either add a new email or an existing email on a different email service (Gmail, Protonmail etc.) Once you've done that remove the old sign in email. Make sure you remember this email or else it will be near impossible to recover your account.

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Step 4: Change/remove billing info

Click here and check to see if there is any billing information on the account. If you don't see any billing information on the account, you're good to go. If there is billing info, replace it. 

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Step 5: Remove devices

Click here and remove all the devices here if there are any.

Step 6: Remove Xbox 360 consoles

 

Go here and click the require profile download button.

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Step 7: More security options/2 step verification

The advanced security settings menu is where you go to set up 2 step. You don't need to do this if you don't want to, but it definitely helps. If you wish to put on 2 step, go here and go through the process. Also right above "Close account" there is an option to remove all trusted devices. Make sure you press that.

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*Credits to @Jammer for this thread*