This will work is the mailbox is in 365:
Sending email from alias
We have an Exchange 2019- Exchange Online Hybrid deployment. I have added an accepted domain [abc.com] and added the domain to O365 as well and our primary domain is [domain.com] . I created a shared mailbox, and added primary SMTP as [abc.com].
My id is [user@domain.com].
When I sent as abc.com , I am getting a permission related NDR. when I send the email as mailbox@domain.com to my personal email address, am getting the email from mailbox@abc.com , but internally am getting the email address from mailbox@domain.com.
Is this an expected behavior ?
Other than enabling “send from alias” , is there anything else I need to do to send emails on behalf of [abc.com].
Does “sendasalias” configuration matter , as the primary smtp is [abc.com].
The aim is that these users should be seeing [abc.com] on sent and received emails.
Thanks