can't change old email address

Welcome Lin Morrisett,

I understand how frustrating it can be when your Microsoft account is still associated with an old email address, and when you try to add your current email address as an alias, you receive a message that it is already in use. 

Before proceeding further, could you please confirm: 

• Is this a personal Microsoft account or a work/school account? 
• Is the current email address already being used as a sign-in alias on another Microsoft account? 

In the meantime, you can try these workaround steps below to troubleshoot the issue:  

Option 1: Review the aliases currently associated with your Microsoft account

• Sign in to your Microsoft account 
• Go to Your info 
• Select Manage how you sign in to Microsoft 

Option 2: Check whether the current email address is already attached to another Microsoft account

• Try signing in with that email address directly 
• Check whether it opens a different Microsoft account profile 

Option 3: Verify whether the email is listed as a contact email rather than a sign-in alias 

• Review the account information under Security and Your info 

I hope the steps above help you deal with your issue.  

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