I have a Small Business Server 2003 which has been working absolutely fine for years.
There are a couple of users who work remotely and although they have the company email address they don't have an account on the exchange server.
It has always been possible to send emails form internally to the external users eventhough they have the same domain. This was achieved deselecting "this exchange organisation is responsible for all mail delivery to this address" in the Default Policy.
Over the last couple of days this is now not possible and if an email is sent form the internal user to the external user they receive a message:
The following recipient(s) cannot be reached:
'email@example.com' on 17/04/2014 13:30
The e-mail account does not exist at the organization this message was sent to. Check the e-mail address, or contact the recipient directly to find out the correct address.
Please help as I have checked all settings and can see no reason why this has stopped working.