[Exim] bounce on failure of dnslookup

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Does anyone know of a way to bounce to a certain specified email address not the sender_address if a mail fails the dnslookup part of a router???

I have set errors_to which works successfully if the dnslookup works and the mailbox is just unavailable, but i cant figure how to bounce to a different address if the router lookup fails. Even if i put a no_more on the end of the router.

This is on a shared mail server, and i do a condition lookup lsearch on a file for the router concerned for the host ip sending the mail and if matches it uses that router and will send errors_to if there are address problems.

Hope this makes sense. I have been trying loads of things

Cheers

Dave
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