"Joseph Gordon" <pdsphx@parishdatainc.com> wrote in message
news:47a341e5$1@newsgroups.borland.com...
> The case I ran into was a user with a firewall. The strange
> thing was if they e-mailed to anyone on the same network
> (like themselves) the e-mail went thru, but outside the network
> and it got blocked.
Firewalls generally do not do that. It is the actual SMTP server's
responsibility instead to verify whether to forward emails to other
networks.
> Is there any SMTP command that would not trigger an
> email but would trigger an error in this case.
I already answered that question in my earlier reply. The only way to
validate whether an email can be sent is to actually attempt to send one.
Even then, you are NOT guaranteed to get an error right away. Unless the
SMTP server knows right away that a target address cannot be reached, then
it has to accept the email from you, end the SMTP session, then attempt to
send the email on its own time behind the scenes and report any errors back
to your inbound email address separately via POP3 or IMAP.
Gambit
