[Mimedefang] Re: DSN

[Paul Russell]

On 23 Oct 2003, Jim McCullars <jim at info.uah.edu> wrote:
 >
 >   Furthermore, the return receipt is generally sent using a null envelope
 >sender (looks like this: <>).  Some sites now refuse email with a null
 >envelope sender, and if your site does, you will never get the return
 >receipts back.  Also, the recipient's email server may refuse the null
 >envelope sender, so he may be unable to send the confirmation even if he
 >wants to.  For example, I use BellSouth DSL at home, and they will not let
 >me send an email with a sender of "<>".  So if I try to send a return
 >receipt, I get a relay error.
 >
 >   HTH...
 >
 >Jim

RFC 2821 *REQUIRES* the use of the null envelope sender address on delivery
error messages. A service provider which rejects messages solely on the basis
of the use of the null envelope sender address is doing its users a disservice,
and they should run - not walk - to the nearest competent ISP.

I can understand why a service provider might reject such messages from its own
"consumer" connections, particularly if its AUP prohibits the operation of mail
servers on those connections.

--
Paul Russell
Senior Systems Administrator
University of Notre Dame