Some synced users missing email aliases

Question

Hi Dear,

I have synced users from on-prem AD to Office 365 using AAD Connect and I'm not able to find email aliases for some of the users. While for others aliases are present same as in EMC 2010. Can anyone let me know why not all the smtp's syncing to Office 365. All the domains are verified and not all users missing aliases but some of the users are missing their aliases. 

Thanks 

Sam

Answer 1

Hi Sam,

For this case, please let me know if you got any update. I will be pleased to further assist you if necessary. 

Regards,

Alan

Answer 2

Hi Sam,

It is my happiness to reply to your case here. 

For your scenario (actually it is the case that some attributes like the AD account alias do not sync to Office 365 while using AAD Connect), it is mostly like to be related to the following reasons. 

1. One or more object attributes that require a unique value have a duplicate attribute value (such as the proxyAddresses attribute or the UserPrincipalName attribute) in an existing user account.

2. One or more object attributes violate formatting requirements that restrict the characters and the character length of attribute values.
3. One or more object attributes match exclusion rules for directory synchronization.

So, I'd like to know if you got any error for the synchronization. If yes, please clarify it and a related screenshot would be better. Also, we have a dedicated article stating this, for your reference you can click https://support.microsoft.com/en-us/help/2643629/one-or-more-objects-don-t-sync-when-the-azure-active-directory-sync-to (there it also provides the corresponding suggestions).

Supposing you do not get any error or the suggestions in the article do not work for you. It is recommended that you try re-syncing it again to see if it works as expectedly. 

Looking forward to your update. I will be pleased to further assist you if necessary. 

Regards,

Alan