We have an Exchange 2003 server here for our users, and I have had some complaints similar to this. Some faculty members try to e-mail a large group of mail.msu.edu users (other staff/faculty and students) and are getting messages back that their e-mails were undeliverable. However, if they e-mail the users individually or in smaller groups, it works fine. We do not have any filtering of mail going outbound. Thanks, Javier -----Original Message----- From: MSU Network Administrators Group [mailto:[log in to unmask]]On Behalf Of John Schwarz Sent: Thursday, December 16, 2004 1:06 PM To: [log in to unmask] Subject: [MSUNAG] SMTP and mail.msu.edu I am attempting to send out a web survey that my department has been commissioned to do via our web server and SMTP. The catch is any address that I send to msu.edu does not make it through. I am assuming I am being filtered out by mail.msu.edu's servers. What do I need to do make this work? Any suggestions are greatly appreciated. Thanks, John Schwarz