kiwi_cam

It sounds to me like your Gateway isn't working at all. Does it work Internally if the client un-ticks the "bypass RD gateway server for local addresses" option? EDIT - I only raise this because I've spent/wasted too much time troubleshooting a gateway that "works internally" only to realise that it wasn't actually being used internally.

That's a great feature I didn't know about either Rob_D. Historically I've always got around this issue by setting up the mail profile as the shared mailbox. When the new mail account wizard asks for an email address, type in the shared one instead of the users email address. The only place to use the user's details is when prompted for credentials. This makes the mail profile under the shared mailbox and you can open the user's mailbox as an additional mailbox. Of course, this means all sent items go into the shared mailbox instead - which might just be moving your problem.