Alias in exchange online visible but does not exisit in onprem AD

Question

Hello,

For one of our users we see an existing alias in our Exchange online portal. In our AD onprem there is no such alias.

Most likely something went wrong during our renaming of this user?

in ADSIEDIT we cannot find the alias. I found some information on deleting the user, but there's a lot of maildata, I do want to explore other possibilities first.

thanks

Answer 1

Hi @ Jan De Smet ，

Great to know that you've already thought of a solution and really appreciate it for your sharing!
By the way, since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others.". and according to the scenario introduced here: Answering your own questions on Microsoft Q&A, I would make a brief summary of this thread:
[Alias in exchange online visible but does not exisit in onprem AD]
Issue Symptom:

For one of our users we see an existing alias in our Exchange online portal. In our AD onprem there is no such alias.

In ADSIEDIT we cannot find the alias. I found some information on deleting the user, but there's a lot of maildata, I do want to explore other possibilities first.

 

The Solution:

I ended up deleting the user object in the onprem AD. Synced manually.

I created a new user with the same SMTP and upn.

I then restored the content from the "old" mailbox to the new mailbox.

https://learn.microsoft.com/en-us/powershell/module/exchange/new-mailboxrestorerequest?view=exchange-ps

this worked perfect.

You could click the "Accept Answer" button for this summary to close this thread, and this can make it easier for other community member's to see the useful information when reading this thread. Thanks for your understanding!

Answer 2

Hi, I ended up deleting the user object in the onprem AD. Synced manually.

I created a new user with the same SMTP and upn.

I then restored the content from the "old" mailbox to the new mailbox.

https://learn.microsoft.com/en-us/powershell/module/exchange/new-mailboxrestorerequest?view=exchange-ps

this worked perfect. Many thanks.

Answer 3

There are scenarios where you can add an alias directly to the cloud user, even when dirsync is in play. Removing it is a bit trickier though. The supported method would be to temporary disable dirsync, make any necessary changes to the cloud object, re-enabled dirsync.

And unsupported and faster, albeit scarier workaround is to delete the user in the cloud, and immediately recover him from the Recycle bin. This effectively makes it a "disconnector", allowing you to manage all its properties directly in the cloud. But again, unsupported, use at your own risk.