Office 365: fix the UserPrincipalName if you synced AD prior to adding the new UPN suffix

Probably like many people, I started testing out Office 365 in phases. One change that we had to make was to add a UPN alias for @domain.org to replace our @domain.local. I was a little leery of this, so I tested out some Office 365 features before adding the domain alias, including adding licenses to about 20 of our accounts.

The problem: those accounts that I just synced up were stuck with the ugly @domain.onmicrosoft.com domain, instead of our nice @domain.org alias. Forcing a resync did not resolve it.

This Technet article explains very clearly how to fix the problem:

Open Windows Azure Active Directory Module for Powershell, and then type in:

Set-MsolUserPrincipalName -UserPrincipalName user1@domain.onmicrosoft.com -NewUserPrincipalName user1@domain.org 

Simple, but I didn’t want to run this dumb command one at a time for each account. Simple enough in powershell, but I ran into a few gotchas so here is the successful command line I ran:

Get-MsolUser -domainname "domain.onmicrosoft.com" | where islicensed -eq $true | %{Set-MsolUserPrincipalName -userprincipalname $_.userprincipalname -NewUserPrincipalName($_.userprincipalname.replace("@DOMAIN.onmicrosoft.com","@domain.org"))}




One thing that took me a minute to remember after several runs with nothing happening is that string.replace() method is case sensitive, so make sure that you properly capitalize the UPN that you want to replace.