How can I disable local delivery for a specific domain

[davebamford]

Hi

I am using ISPconfig 3 and have searched the manual and the forum for a way to disable local delivery for a specific domain.

The reason I need to do this is that I am migrating a user/domain from a dying server to ISPconfig and there are over 200 mailboxes. So far I have migrated about 20 mailboxes and they fetch their mail from the old server with POP. But if any of them try to send email to a non-migrated user it fails as there is no mailbox.
I have tried setting the old server as a destination for that domain with advanced email routing but it doesn't seem to work. Been through the postfix manual but am lost.

Please can anyone help

Thanks

Dave Bamford