Exchange 2007 sending from accepted domain

Question

We're opening an US office shortly and i've added the new domain (domainus.com) to our exchange 2007 environment as an "accepted domain" and added some addresses as SMTP addresses to a few members who can receive properly - yey :).

We want to send from these addresses too but I can't figure out how to make this work, I get the error:

"You are not allowed to send this message because you are trying to send on behalf of another sender without permission to do so. Please verify that you are sending on behalf of the correct sender, or ask your system administrator to help you get the required permission. "

I'm not well versed in exchange so i'm not sure what to search for to try and figure it out. I've tried:

Adding themselves to send to "Delivery options > send on behalf" and I edited the default email address policy for the organisation (which wasn't being applied before.... so I don't think it would make any difference).

Any suggestions welcomed.

Thanks in advance.

Answer 1

On the user account, in Active Directory, under Security, under the SELF account, select the Manage Send As Permission option.

Answer 2

I know it isn't much help, but I was having the same issue, and getting the same error. I ran across this page that lists 4 ways to do it. None of them are what you would expect, except for the application that you have to purchase.

I do think if you have a gmail account that you could send as the alternate email address, and all replies etc would come back to the exchange account.