Is spam filtering done on outgoing emails?

This article is intended for users who still read email on legacy SEAS servers. It does not apply to Google@SEAS.

Our SMTP mail servers ( have a spam-filtering function much like our incoming mail servers, which use Proofpoint. The way you send emails will not be affected; you continue to send emails the same way you already do.

However, there are rare times that your email is mistakenly considered spam (a false positive), and you will get a warning about it. If you use graphical email program (Thunderbird, Webmail, Apple Mail, etc.), you will get a pop-up box to warn you about it:

Spam Error Message

If you use a text-based email program (Pine, Mutt, etc.), you will get a "Returned Mail" in your inbox, and it will say:

----- The following addresses had permanent fatal errors -----
(reason: 550 5.0.0 The SEAS mail filter blocked this message as spam. If it is a legit message, please contact and we will release the message and update the filter.)

If you get a warning when you try to send a legitimate email, you can contact CETS to have the message released. We will release the message and also update the filter.

The scoring is done automatically by software, not by a person looking at your outgoing emails. Messages that are considered spam are "quarantined". If it was a false positive and you request to release the message, we generally only look at the headers (from, to, date, and subject) when we release the message. However, we may look at the body of a quarantined message if we're trying to troubleshoot a problem or if it appears that your account is actively being used to send spam.

We put spam filtering on our outgoing mail servers to be good citizens, to protect Penn's reputation and to protect your reputation. Criminals have sent spam and/or phishing emails from cracked SEAS accounts in the past. Typically they collect account credentials using a trojan, keylogger, or phishing, then use the account to send spam to everyone in the owner's address book and many more people. By having a spam filter on our outgoing servers, we can block this. In turn we avoid being blocked ourselves by other entities/organizations.

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