The best way to diagnose email issues is to start for the beginning and go back to the basics. Verify that your MX server for your name space can be resolved, do this by atttaching your NSLOOKUP utility to some down stream DNS server and set your type to MX and verify that your mail server can be resolved correctly, make sure that your reverse lookup also works, some mailers wont send messages unless a forward and reverse lookup resolve succesfully. Manually testing using Telnet using port 25 is also a good check to see if you can open a session and send data. Make sure that your mailer is NOT open for relaying, A lot of companies use an internet DB to check if your mailer is black listed for allowing relaying, so make sure this is tightened up. -----Original Message----- From: Martin Chen [mailto:martinhr@xxxxxxxxxxxxxx] Sent: Monday, April 07, 2003 10:49 AM To: [ISAserver.org Discussion List] Subject: [isalist] Exchnage server publising by ISA causing some emails been rejected. http://www.ISAserver.org Dear all, Did anyone ever had a problem that some emails from specific domains were always been bounced back. These domains can received email sending from our server. But they can't send email to us. Some domains will get a error message but some domain will receive nothing ( the email is gone without any notice). I'm using ISA sp1 ( I using the first version sp1 last year. Then I found lots of mail been bounced back. Then I using newest sp1, it fix some domains' emails. But not all of them. My email server is Exchange 2k with sp2 and Win2k server with sp3. Thanks! Martin Chen Tel: 886-2-8227-1669 ext 2202 Fax: 886-2-8227-1690 Email: <mailto:martin.chen@xxxxxxxxxxxxx> martin.chen@xxxxxxxxxxxxx MSN messenger: <mailto:martinhr@xxxxxxxxxxxxxx> martinhr@xxxxxxxxxxxxxx Free Trial Software: Monitor & Manage Web Use with SurfControl Web Filter for MS ISA Server http://www.surfcontrol.com/go/zisadl1 ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=isalist ISA Server Newsletter: http://www.isaserver.org/pages/newsletter.asp ISA Server FAQ: http://www.isaserver.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Exchange Server Resource Site: http://www.msexchange.org/ Windows Security Resource Site: http://www.windowsecurity.com/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------ You are currently subscribed to this ISAserver.org Discussion List as: gmaks@xxxxxxxxx To unsubscribe send a blank email to $subst('Email.Unsub')