System Overview

Washington University uses two redundant Ironport C360's and two redundant Microsoft LDAP directory servers for anti-spam, anti-virus, and routing all email destined for email addresses. One set of servers is located on the Danforth campus. The other set is located at the medical school campus. This offers geographic redundancy for maximum server availability.

Mail Flow Overview

    •    Mail arrives into the Ironport server.
    •    The reputation of the sender is verified against SenderBase (An Ironport Company).
    •    The email is anti-spam and anti-virus scanned.
    •    LDAP servers are contacted to determine how to route mail to the mail-store.
    •    DNS servers are contacted to find the MX server for the mail-store.
    •    Mail is delivered to the mail-store.
All email will come from If you have any "email firewall" devices make sure to not rate limit or block email from this IP range.

What if my mail has been improperly marked?

What should you do if your good email has been marked as spam or your spam email has not been marked at all? Ironport has two email addresses that can be used to report false- positives and false-negatives.
    •    Report undetected spam to:
    •    Report false-positives to: •
IMPORTANT: You must include the full email header. The full header looks like 

Microsoft Mail Internet Headers Version 2.0 Received: from ([]) by with Microsoft SMTPSVC(6.0.3790.1830); Thu, 21 Dec 2006 11:15:51 -0600 Received: from ([]) by with SMTP; 21 Dec 2006 11:15:41 -0600 Message-Id: <5jdenl$> X-IronPort-Anti-Spam-Filtered: true X- IronPort-Anti-Spam-Result: Ao8CAFpQikWA/HhX/2dsb2JhbAA X-IronPort-AV: i="4.12,200,1165212000"; d="scan'"; a="18:sNHT18868577"
To: From: Subject: This is a full email header Return-Path: X-OriginalArrivalTime: 21 Dec 2006 17:15:51.0718 (UTC) FILETIME=[AA744C60:01C72523] Date: 21 Dec 2006 11:15:51 -0600

Full headers must be included if you are reporting improperly marked email to Ironport. Failure to include the full header will result in your submission being ignored.

What if I have problems receiving email?

The first thing you should do is contact your department IT staff. If the IT staff determines the problem is not caused by the local departments system, they will contact NSS directly to resolve the problem.
If this is a serious emergency you can contact NSS directly.


What if I want to change my email address or if my mail is forwarding to the

wrong address?

Contact your department office. Students may also change their own information with WebStac. You can read more about this at

Individual Department Settings

The Ironport C360 offers individual departments the ability to do per domain settings. These setting are based on the domain that is returned after the LDAP lookup is performed. For example, the final destination for We can make customized settings for all mail destined for The following settings are adjustable:
    •    Ability to Deliver, Drop, or Bounce mail positively identified as spam
    •    Ability to Deliver, Drop, or Bounce mail which is suspected as spam
    •    Ability to adjust settings used to identify spam positive mail (range of 1 to 100)
    •    Ability to adjust settings used to identify spam suspect mail (range of 1 to 100)
    •    Ability to adjust how mail is tagged as spam. You have the options to modify the subject 
of the email or add x-headers into the header of the email. 


Mail Server Names