Question : 500 line too long

I have a client that cannot send emails to us.  I am running Exchange 2003 with a Watchguard Firewall.  I can receive the email in Gmail and hotmail but not from our server.  i can email the client but the clients email fails when she tries to send it back.  The error is below:

----- Transcript of session follows -----
... while talking to mail.kbkinsgroup.com.:
>>> DATA
<<< 500 Line too long
554 com>... Remote protocol error

Final-Recipient: RFC822; jessicakimes@kbkinsgroup.com
Action: failed
Status: 5.5.2
Remote-MTA: DNS; mail.kbkinsgroup.com
Diagnostic-Code: SMTP; 500 Line too long
Last-Attempt-Date: Wed, 18 Oct 2006 11:37:17 -0400 (EDT)

Received: from PGIA13@aol.com
    by imo-m16.mx.aol.com (mail_out_v38_r7.6.) id n.bc2.460591a (52464)
     for com>; Wed, 18 Oct 2006 11:37:10 -0400 (EDT)
Return-Path:
Received: from  webmail-da18 (webmail-da18.webmail.aol.com [205.188.212.213]) by
ciaaol-d09.mx.aol.com (v113.6) with ESMTP id MAILCIAAOLD093-ccf045364a26199;
Wed, 18 Oct 2006 11:37:10 -0400
References: <93FD03736835694D9BE1AE02A42105014BD67D@manning.KBK.LOCAL>
To: jessicakimes@kbkinsgroup.com
Subject: Re: Express Automotive Transport LTD
Date: Wed, 18 Oct 2006 11:37:10 -0400
In-Reply-To: <93FD03736835694D9BE1AE02A42105014BD67D@manning.KBK.LOCAL>
X-MB-Message-Source: WebUI
MIME-Version: 1.0
From: pgia13@aol.com
X-MB-Message-Type: User
Content-Type: multipart/alternative;
 boundary="--------MB_8C8C0E268ED52B7_A10_130C3_webmail-da18.sysops.aol.com"
X-Mailer: AOL WebMail 20836
Received: from 68.248.101.198 by webmail-da18.sysops.aol.com (205.188.212.213)
with HTTP (WebMailUI); Wed, 18 Oct 2006 11:37:10 -0400
Message-Id: <8C8C0E268EFB50B-A10-A0D8@webmail-da18.sysops.aol.com>
X-AOL-IP: 205.188.212.213
X-Spam-Flag: NO

Answer : 500 line too long

Well that isn't an Exchange server answering...

If I telnet to that domain I get this:

220 mail.kbkinsgroup.com ESMTP Service ready
elo
500 Syntax error, command unrecognized
ehlo domain.net
250-Requested mail action okay, completed
250-SIZE 20000000
250-ETRN
250-8BITMIME
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250 OK

I should get this:

220 mail.domain.net Microsoft ESMTP MAIL Service, Version: 6.0.3790.1830 ready at
  Wed, 18 Oct 2006 23:39:39 +0100
ehlo domain.net
250-mail.domain.net Hello [192.168.1.103]
250-TURN
250-SIZE
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-BINARYMIME
250-CHUNKING
250-VRFY
250-X-EXPS GSSAPI NTLM LOGIN
250-X-EXPS=LOGIN
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250-X-LINK2STATE
250-XEXCH50
250 OK


Therefore something else is answering SMTP traffic for you and is the cause of the problems. Firewall, anti virus and anti spam applications are the usual suspects.

Simon.