I've got a Exchange server running a few email domains. I don't get any problems recieving email on any of those domains. However, I can only send email from one of them.
If I try using the From option in Outlook to send from another domain (same user name), I get the error below:
Delivery has failed to these recipients or groups:
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.
Diagnostic information for administrators:
I have setup MX records, Certificate, accepted Domains and changed the default email policy to handle the email domains.
I think this is an Exchange error but I'm not trying to send on behalf of the email address in the error message, I'm trying to send an email to this address! Whats the fix?
Thanks in advance.