Hi @@Adorney, Frank
Based on my testing, if your calling app has one of the UserAuthenticationMethod.Read.All
or UserAuthenticationMethod.ReadWrite.All
application permissions, then you should be able to retrieve the user's email authentication method, even if the target user has the Administrator role.
Please try running the Get-MgContext
command to see if you have the above permissions in your app-only context.
Hope this helps.
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