Users having emails as @mycompany.onmicrosoft.com

Question

In my environment we have found that there are few users that have emails as @mycompany.onmicrosoft.com on Azure AD.

However we have checked their UPN attribute in AD is updated as@ mycompany.com.

What could be the possible reason and how can I resolve this so that the email addresses could become as @mycompany.com on Azure AD as well.

Azure AD Connect is already configured to sync users from on-prem AD to Azure AD and for most of the users UPN is resolving to @mycompany.com but for few users it still remains as @@mycompany.onmicrosoft.com on Azure AD.

Answer 1

It's normal to have secondary email addresses associated with the default @tenant .onmicrosoft.com domain. If you are also seeing some users with primary SMTP using said domain, it's likely because of missing values on-premises. UPN is usually the last thing that will be used for the value of Primary SMTP Address, instead the proxyAddresses, mail and/or mailNickname attributes are used with precedence. Refer to this article for more detailed explanation: https://learn.microsoft.com/en-us/troubleshoot/azure/active-directory/proxyaddresses-attribute-populate