Hi FuzzyBunny,
Thank you for coming back and sharing the workaround you found. I understand why the missing Make primary option was confusing, especially since the newly added Gmail address was already verified and could be used to sign in.
Email addresses associated with the same Microsoft account are called aliases. They share the same password, contacts, storage, subscriptions and account settings. The primary alias is the address displayed on Microsoft devices, such as a Windows PC or Xbox. For more information, please visit: Which account do you want to use?
Microsoft also provides general guidance for adding, removing, or updating addresses associated with an account here: Change the email address for your Microsoft account
Your workaround may be useful when both addresses are external, non-Microsoft addresses. However, anyone trying it should be especially careful before removing an alias. Please note that an alias using a Microsoft domain, such as @outlook.com, @hotmail.com, @live.com or @msn.com, is permanently deleted when removed from the account and cannot be associated with a Microsoft account again. It is also a good idea to confirm that the replacement address is verified and that the account has up-to-date recovery information before making changes.
More information about aliases and the removal warning is available here: Add or remove an email alias in Outlook.com
I’m glad you found a method that worked for your Verizon and Gmail addresses and thank you for documenting it for others who may encounter the same interface. If Change does not work for another user or if the address involved uses a Microsoft-owned domain, contacting Microsoft Support would be safer than removing the alias as a test. Thank you so much for your understanding.
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