Unable to create alias on Shared Mailbox in O365 after hybrid join

Question

I'm looking for the best practicee on how to add alias, before joining to hybrid I could add alias for single or shared account in O365/Exchange online but after hybrid join, I cannot see a way to add alias for shared account in O365. Each time I add alias for shared account in O365/Exchange I gets a error says  "We couldn't save your changes. Please try again. "If I would like to add alias for user account, I cannot do it via the O365/Exchange online, I have to go to local AD>User>user attribute>Proxy address> smtp:[email protected] that's how I can get alias for user accounts

My environment:  One AD forest with One Domain (local) 1 O365 Tenant with 25 domains

There isn't on-premise Exchange server. Does anyone have any suggestions on how to add an alias to shared account in o365 if we have Hybrid join.? 

Many thanks

Answer 1

I have to go to local AD>User>user attribute>Proxy address> smtp:[email protected] that's how I can get alias for user accounts

This is the only way that you can add aliases for email accounts for those users that you create on-premises if you create the shared mailbox directly on your Exchange Online and managed the aliases directly on your Exchange Online web

Hope this help.

Answer 2

I couldn't add alias to my shared mailbox. I was getting error saying domain is not accepted. after digging I found one of the shared mailbox had an alias and the alias domain doesn't exist in my environment anymore.

after removing that alia I could add more into to all shared mailbox.