Bad Alias Address in Federated User's ProxyAddresses

[Jim Sepanik]

We are using ADFS to create Office 365 accounts and for authentication. When a user is created, 2 aliases are created. One with @tenant.onmicrosoft.com and @tenant.mail.onmicrosoft.com. These are then synchronized to our on premise AD.

Currently we are migrating from GroupWise to Office 365. When a user is migrated the tool creates a rule that forwards mail to the first.last@tenant.onmicrosoft.com.

I have a user, jane.smith@ourdomain.com. When she was created in Office, the aliases were created as joe.doe@tenant.onmicrosoft.com and jane.smith@tenant.mail.onmicrosoft.com. She can now receive Joe Doe's forwarded email. On our on premise AD, she has the proper proxyaddresses jane.smith@ourdomain.com, jane.smith@tenant.onmicrosoft.com and jane.smith@tenant.mail.onmicrosoft.com. Since we are using ADFS we cannot modify these addresses from the Admin console, and the on premise AD has the correct addresses.

I expect that I can repair this in Azure AD, but there is no option to replace the proxyaddresses in the set-azureaduser commandlet.

Any suggestions will be welcomed, I would prefer to have the powershell commands to do this, but a manual process will work, too.

[#2]

So to understand correctly, the jane.smith@tenant.onmicrosoft.com and jane.smith@tenant.mail.onmicrosoft.com are only showing in local AD and not in Azure AD?

[#3]

There is a "workaround" that allows you to play with the aliases of a synced user, to an extent. Namely, you can use the following:

Set-Mailbox user@domain.com -WindowsEmailAddress newuser@domain.com

This will set newuser@domain.com as the primary SMTP, while preserving user@domain.com as secondary. There is no way to remove any aliases though, unless you disable DirSync. Well, there is, but you will not like it - you need to make the user a "disconnector", by deleting it and the recovering from the Office 365 recycle bin. Not supported in any way :)