Out of Office Assistant

[Emmet]

Out of office assistant is set up to forward all incoming
email to the users home email address.
All internal email is being forwarded ok, but all external
email will not forward to the home user.

The recipients Exchange Server configuration is set up to
deliver all incoming messages to both users but doesn't seem
to work for external incoming email.

Does anyone know a fix for this please!!
Thanks,
Emmet
emcgloin@ergoservices.ie