Mar 21 2019 06:13 PM - edited Mar 21 2019 07:45 PM
Scenario:
1 regular mailbox for user@contoso.com
1 shared mailbox shared@contoso.com
user have send on behalf rights to shared mailbox shared@contoso.com
requirement is to block user@contoso.com from sending emails and force him to send mails using shared mailbox shared@contoso.com
is this possible?
Mar 21 2019 07:43 PM - edited Mar 21 2019 07:44 PM
You mean prevent him from sending messages with his own account? No way to do that I'm afraid. The only thing you can do is create a transport rule that blocks the messages after they are sent via the client.
Mar 22 2019 06:37 AM - edited Mar 22 2019 06:56 AM
you can do it using third-party tools/services.
Have a look at SmartReply cloud service. It seems that "Uncoditional address rewriting rule" will fit your requirements.
If you run only Outlook for Windows, take a look at SetFrom add-in.