>From an outside (stranger) network.
From: Eric [mailto:seag...@gmail.com] Sent: Tuesday, July 06, 2010 2:56 PM To: MS-Exchange Admin Issues Subject: Re: Open relay... Kind of I haven't used Exchange 2003 in a while, but are you testing this using telnet from within your network? I know some other mail systems I've used (Postfix) can allow only certain IP's or a local lan to send mail. On Tue, Jul 6, 2010 at 11:49 AM, <gro...@beachcomp.com> wrote: Hi all, Having one of those days. Just noticed our exchange server doing something funky and wondered if I was missing something. Using an Exchange 2003 machine, and for some reason it's allowing local to local e-mail remotely and w/o authentication. What am I missing here? Here's a telnet session from a REMOTE machine: 220 Server.Domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.46 75 ready at Tue, 6 Jul 2010 14:35:41 -0400 HELO 250 Server.Domain.com Hello [208.00.00.99] MAIL FROM:t...@domain.com 250 2.1.0 t...@domain.com....sender OK RCPT TO:t...@domain.com DATA 250 2.1.5 t...@domain.com 354 Start mail input; end with <CRLF>.<CRLF> TEST . 250 2.6.0 <serverox7nyekzgzuny00000...@server.domain.com> Queued mail for delivery 220 Server.Domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.46 75 ready at Tue, 6 Jul 2010 14:42:21 -0400 HELO 250 Server.Domain.com Hello [208.00.00.99] MAIL FROM:t...@domain.com 250 2.1.0 t...@domain.com....sender OK RCPT TO:t...@test.com <mailto:to%3at...@test.com> 550 5.7.1 Unable to relay for t...@test.com 220 Server.Domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.46 75 ready at Tue, 6 Jul 2010 14:43:39 -0400 HELO 250 Server.Domain.com Hello [208.00.00.99] MAIL FROM:t...@test.com <mailto:from%3at...@test.com> 250 2.1.0 t...@test.com....sender OK RCPT TO:t...@test.com <mailto:to%3at...@test.com> 550 5.7.1 Unable to relay for t...@test.com 220 Server.Domain.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.46 75 ready at Tue, 6 Jul 2010 14:45:37 -0400 HELO 250 Server.Domain.com Hello [208.00.00.99] MAIL FROM 501 5.5.4 Unrecognized parameter MAIL FROM:t...@test.com <mailto:from%3at...@test.com> 250 2.1.0 t...@test.com....sender OK RCPT TO:t...@domain.com 250 2.1.5 t...@domain.com DATA 354 Start mail input; end with <CRLF>.<CRLF> TEST . 250 2.6.0 <serverfraqbc8wsa1xv00000...@server.domain.com> Queued mail for delivery Thanks for your input.