Change or add SMTP address to O365 user

2017-12-11T16:11:33+00:00 June 6th, 2015|Office 365|

I was setting up some testing in my labs recently and synced a user from AD to O365. I noticed this user had the primary email address of the onmicrosoft domain which I didn’t want.

When I tried to change this in Exchange online I was presented with an error:

Now I don’t have exchange configured on premise as a hybrid, which is where I would immediately go so I turned to PowerShell but got quite a similar error in there too.

 

 

I then came across this: https://support.microsoft.com/en-us/kb/2492140 – ah! So I headed into ADUC, onto my user, Attributes tab, found ProxyAddresses and added what I wanted.

A couple of notes:

  • If you don’t see the Attributes tab make sure you have Advanced Features ticked under the View menu of ADUC
  • If you prefix your address with SMTP it will become primary, if not it will be set as an alias
  • You can add as many alias’ as you wish

Here’s what mine looked like:


 

After a DirSync/Azure AD Sync ran my primary SMTP address updated and my extra email address was also added.

Hope it helps!