i have exchange 2000 server, but our office cannot send to yahoo domain only the mail only hold on the server queue, no any reject mail to client how can i do

You need to take a look at your Exchange SMTP logs, it will show why yahoo was rejecting. Logging the SMTP Service http://www.msexchange.org/tutorials/Logging_the_SMTP_Service.html Or do a telnet session to yahoo's mail server and try to send mail, you will likley get a reject with the reason right away. from command prompt nslookup -type=mx yahoo.com telnet c.mx.mail.yahoo.com 25 helo mail from:user@mydomain.com rcpt to:user@yahoo.com data subject:test . . James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

when i type below command , it will show lost the connection telnet c.mx.mail.yahoo.com 25 helo mail from:user@mydomain.com rcpt to:user@yahoo.com data subject:test

What does your SMTP Logs on the server say? Any NDR? Anything in queue viewer?Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

It says lost the conenction right after you do telnet c.mx.mail.yahoo.com 25 or after you do the other subsequent commands? I would also check to see if you are blacklisted anywhere, enter your mail servers public ip. http://www.mxtoolbox.com/blacklists.aspx James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Our server not list on the black list

No any NDR, and the Email hold on the quene, cannot outgoing

after i do telnet c.mx.mail.yahoo.com 25

i get the smtp log but how to read?

what's the last error of that queue? You could paste the related part of smtp log here to see if someone can help.

If you are getting connection lost right after you telnet to yahoo's mx server it could be that their rejecting your IP. I would open a ticket with yahoo. Yahoo mail delivery issues form http://help.yahoo.com/l/us/yahoo/mail/postmaster/forms_index.html James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com