What is the functional or security reason for verifying that
the domain exists, in terms of ASP.
The short answer is in 3.2, where there's a different answer for "I
dunno" and "doesn't exist".
As I recall, it's always been that way, but that's a good question.
There's certainly plenty of reasons to be wary of mail with a return
address that doesn't exist, but baking that into ASP does feel like
mission creep, doesn't it?
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