Shine, Gary wrote:
> How exacvtly does this veryify the sender?
>
> # Deny unless the sender address can be verified.
> require verify = sender
>
> I cannot imagine it can very every e-mail address out there so is it
> something to do with verifyoing the headers or looking up on the receiving
> machine?
>
> Confused and documentation is vague.
>
You should read this:
http://www.exim.org/exim-html-4.66/doc/html/spec_html/ch40.html#SECTaddressverification
It's not so vague at all ("The first stage of address verification,
which always happens, is to run the address through the routers, in
verify mode.") It tests if routing can succeed, so if the domain doesn't
even exist, it won't be accepted for example.
