We just started to use the Zimbra Server Open Edition version 7.2 in our company and we use Outlook as the main client application.
We have an AD with which we authenticate our users and we created aliases for some users something like email@example.com, firstname.lastname@example.org.
Now, the management is asking if possible for those users to be able to send emails as their aliases ... A solution to the problem was to enable the FROM field when a new message is composed in Outlook and the user could type the email address that he wants to appear in the sent field and the user at the other end would receive a message with the On Behalf Message.
I managed to find "hack" in the forums which will allow me to remove the On Behalf Message but the problem with this now is that the user can type any email address he wants even send a message as the president of the company ...
I unchecked the "Allow sending email from any address" setting in the preferences of those users and typed the alias email address for that user but still no go ... So how can I allow those users to send emails as their aliases ONLY ??