This is using MS Exchange 2010 server. This Exch server is hosing few public email domains, for example, @abc.com, @def.com, etc. @abc.com used to be the primary email domain. Recently, we purchased and successfully registered for a new public email domain, called ghi.com. This new email domain also successfully configured in exch as accepted domain, plus some other mx settings in NS server. We verify that mails sending/receving from this new @ghi.com is working fine.
However, if we added this @ghi.com as the secondary smtp email address besides existing @abc.com, then mails failed to send out. For example, userA already got userA@abc.com configured in his mailbox. Now, we added userA@ghi.com as the secondary email address in userA mailbox property.
Then on UserA MS Outlook, we create additional From email address, called userA@ghi.com. Now, when replying email, userA can choose between send as userA@abc.com or userA@ghi.com. Mails sending as userA@abc.com works perfectly. However, attempt to send as userA@ghi.com, failed with following error:
You can't send a message on behalf of this user unless you have permission to do so. Please make sure you're sending on behalf of the correct sender, or request the necessary permission. If the problem continues, please contact your helpdesk.
Any configuration step i missed out? Any help is appreciated.