Forum Discussion

Lefty's avatar
Lefty
Copper Contributor
Jan 17, 2025

Exchange changes not propagating back to 365, but only for one account

So, I have a Tenant where, for reasons known only to previous admins, when company rebranding occurred, rather than setting up the new email addresses as aliases on the existing user mailboxes, a new mailbox for the new domain was created each time.
As a number of people have multiple accounts with multiple mailboxes which I am currently merging together (using BitTitan MigrationWiz, which seems to be doing its part just fine).

Now, for the purposes of this discussion there are three domains

olddomain.com (the email domain before the rebranding, emails still get sent to that address daily)
newdomain.com (the current preferred email domain)
other.com (a domain they purchased and added to the Tenant but are not using, I am using it to park the older mailboxes after their contents have been merged into the current one).

My procedure has been
1) set email address removed for privacy reasons as an alias on the olddomain.com account (for convenience in setting up migrationwiz)
2) Do a pre-stage merge of most of the olddomain.com mailbox into the newdomain.com mailbox
3) In 365 Admin, change the primary email of the olddomain.com account to be otherdomain.com
4) In Exchange, go to what is now the otherdomain.com mailbox and delete the olddomain.com alias from it
5) In 365 Admin, add olddomain.com as an alias to the newdomain.com 
6) Finish the merge with MigrationWiz

Now this worked apparently flawlessly for 7 people, then I encountered a problem with the 8th
Everything went fine up until step 5, when I discovered that despite deleting the olddomain.com alias in Exchange, it still exists as an email alias in the email address removed for privacy reasons account (the one attached to the old maibox) in 365 Admin, so I cannot assign it as an alias to the email address removed for privacy reasons account

Putting things back seems to work fine, changes I make in 365 admin seem to propagate pretty much instantaneously to Exchange, but the opposite is not the case. But so far only with this one account, not only have I executed the above procedure successfully with 7 previous users on this tenant, but I've done it with one more since this problem case popped up (and I've tried the problem case again since that successful operation, thinking it might just have been a glitch) but it still doesn't work.

Does anybody have any ideas?

  • Lefty's avatar
    Lefty
    Copper Contributor

    Well, I tried the same process again at 11pm that night, and it went through without a hitch.

    So it seems it was a temporary glitch, I'd put it down to just a connection failure between exchange admin and 365 admin, but exactly the same process worked fine for a different user during the "glitch", so it seems to have been more selective than that.

  • Lefty's avatar
    Lefty
    Copper Contributor

    I don't seem to be able to edit my post to get around the "helpful" redaction of completely made up emails. (How many people are actually called "person"?)

    Anyway, in step (1) it is person at otherdomain, and then the paragraph after the list I am saying that
    oldomain is still an alias on person at otherdomain, so I can't add it as an alias to the newdomain mailbox.

  • A bit hard to follow with all the "helpful" redactions from the forum software, but let's give it a try. First thing that comes to mind is to check the UPN of the user - there is a "hidden" email address policy in ExO that requires at least one email address to match the UPN value, be it primary or secondary one. Apart from that, check for any sync errors in AAD Connect/Cloud Sync, and verify that the deletion is correctly reflected on the object in the Metaverse. If everything seems fine therein, the issue might be on MS side, a support case won't hurt.

    • Lefty's avatar
      Lefty
      Copper Contributor

      What are the redactions? I didn't use any real domains or user names so there is nothing really to redact, but I guess the forum software doesn't know the difference?

       

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