User object not synchronized anymore

[woelki]

Hey guys,

we have one user object which seems not to sync anymore. Some days ago the sync was fine for the mailbox marketing@contoso.com
Then we migrated the mailbox from OnPrem to EOL. Now we recognized that the default onmicrosoft email address changed, it is now marketing1234@contoso.onmicrosoft.com
I wondered about it so I added marketing@contoso.onmicrosoft.com and marketing1234@contoso.onmicrosoft.com OnPrem. I hoped it would sync and afterwards I can remove the unwanted address.

The AAD Connect shows no errors, the user object is still in the OU which is activated for sync.

What would be the smoothest way to fix this?

Kind regards,

woelki

[#2]

Most likely you have a duplicate object, which explains both the renaming of the alias, and the fact that the object doesn't seem to sync anymore. Read here: https://docs.microsoft.com/en-us/azure/active-directory/hybrid/tshoot-connect-objectsync

https://docs.microsoft.com/en-us/office365/troubleshoot/administration/duplicate-attributes-prevent-...

[#3]

I didn't thought that you might be right, but you are. I always looked for OnPrem, but somebody created a distribution group in the cloud with the same proxyadress.

Unfortunately a simple cleanup did not help. Even not with initial sync. Troubleshooting in AAD Connect shows no errors. Very odd.

Any further ideas?

Kind regards,
Christian

[#4]

If you have removed the duplicate object, the issue should be solved after the next sync. In case the original object's attributes were replaced via the "resiliency" feature as detailed in the article above, you might need to replace them back. Other than that, you can ignore any errors showing in the O365 portal - it's known to have latency issues.

[#5 · Accepted solution]

I could recognize, that the issue did appeared for other accounts as well. The solution was to restart the AAD Connect and Exchange Hybrid server. Now attribute changes are successfully synced again.

Thanks anyway.

Kind regards,
Christian