Forum Discussion
What is the difference between "OtherMails" and "ProxyAddresses" when using PowerShell?
Actually, when you rename the user, the UPN and Primary SMTP address of the user get updated. In this case, the old primary email address is added as secondary email address. In Azure AD, the Primary SMTP Address and Alias Email Addresses are available in the ProxyAddresses attribute. Refer the below post to know more about how the proxyAddresses attribute is populated in Azure AD.
- https://docs.microsoft.com/en-us/troubleshoot/azure/active-directory/proxyaddresses-attribute-populate
The OtherMails property is not related with the SMTP email address. This is a different property which populates the user's alternate email address which can be configured through Azure AD portal. Initially, I thought this is the email address that can be used for MFA or SSPR authentication, but this is not true since the email address for the Multi-factor authentication or SSPR is stored in different place.
Hope, the OtherMails property is currently returns only the Alternate email address which is configured under the user's contact information. Refer the below image.
Hope, VasilMichev provide more insight.