[Exim] Implementing "whitelist" feature for sender addresses…

Hi there,

I have the following in my exim.conf (4.14):

  accept  senders       = ${lookup {$sender_address} lsearch {EXIM_VIRT_DOM_DIR
/$domain/whitelist} {$sender_address} {}}
          domains       = +local_domains

This works fine AS LONG AS the file is available. How do I handle situations
when the file is missing? Of course I would like to pass to the next ACL
statement in these cases...

Thanks for any help,

Ralf

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