Send on behalf rights

[Guest]

I have a few users here who have rights to a shared mailbox. A new user was
given Full rights to the mailbox like the others have. However, when the user
tries to send on behalf of the mailbox she gets a message stating that she
doesn't have permissions. The other users do not have the send of behalf of
rights in AD nor are the listed as a delegate for the mailbox in Outlook.
They do not want the email saying that it's sent on behalf of either. They
want it to look like it's directly from the shared mailbox. How can I
accomplish this?

 

[Guest]

in outlook you have the "send on behalf" permission which is granted through
delegation at the user's level and you got the "send as" permission which
must be granted on the exchange server level.
I guess you need to give "send as" permission to your users of the shared
mailbox.

http://office.microsoft.com/en-us/outlook/HA100750811033.aspx
http://technet.microsoft.com/en-us/library/aa998291.aspx
http://support.microsoft.com/kb/895949