HELP!!! URGENT POP3 relay problem

  • From: vsina@xxxxxxx
  • To: exchangelist@xxxxxxxxxxxxx
  • Date: Thu, 6 Feb 2003 12:15:03 -0700

I am desperate so I would greatly appreciate some assistance with the
following problem:

We run Exchange 2000 using POP3 with Netscape as the client.  Several
months ago our mail server was used as a open relay station.  We have
closed the relay but ever since then we've been having the following

Users are able to receive their exchange email regardless of which ISP
they are using.  All users are able to send emails locally through their
ISP to anyusername@xxxxxxxxxxxxxx  However, only users who are using
dial-up from home are able to send email messages to domains other than
ours.  When ssers with cable modem/DSL for ISP attempt to send email to a
domain other than ours they receive the following error message: "5.7.1
unable to relay for username@xxxxxxx please check the message recipients
and try again".

Our default SMTP relay restrictions are set up for "Only the list below"
and is granted access (NOTE: we do not have STMP connectors
setup; do we need to?).  The "Allow all computers which successfully
authenticate to relay, regardless of the list above" box is checked.  I
know that in Outlook Express there is a selection for "my server requires
authentication", but I don't see such a setting in Netscape.  Is this the
problem?  We also have a firewall in place.  Could our firewall be the

I have read through tons of stuff on the web and gotten some great
information, but I still haven't resolved the issue.  PLEASE HELP!!!


Other related posts: