Why does pangea refuse to accept email from Eudora, Outlook, or other program on my PC or Macintosh?

Last revision February 2, 2006

Unscrupulous individuals known as "spammers" try to use other computers as relay sites to send junk email messages. In an effort to prevent pangea from being abused this way, the email system on pangea has been configured so that it refuses to forward any email that comes from a non-Stanford computer and is also addressed to a non-Stanford site. Email either has to come from a computer directly connected to Stanford's network, or it has to be addressed to a computer directly connected to Stanford's network, before pangea will accept it and send it. This same filtering rule is used by the central campus server.

When you use a Macintosh or PC based email program like Eudora or Outlook, with pangea designated as your mail server, remember that although incoming email is addressed to user@pangea, outgoing mail from your Macintosh or PC is not from pangea. Rather, it is from your Macintosh or PC, with whatever internet address that computer has, and is only relayed by pangea.

Therefore, if your Macintosh or PC is not directly connected to the Stanford network, mail sent using pangea as the mail server will be rejected by pangea unless the final destination is a Stanford address. This is due to the anti-spamming rule to refuse forwarding from one non-Stanford address to another.

For example, if you connect your Macintosh or PC at home via modem to an internet service provider such as Earthlink, and specify pangea.stanford.edu as the POP (incoming email) and SMTP (outgoing email) server in Eudora, then you can send email from that Eudora program to anyone at any Stanford site, but pangea will refuse to relay any email from you to a non-Stanford site.

How to fix the problem

If you have a computer that stays at home or another institution (not alternating between Stanford and the other site), then the simplest fix is to see if your internet service provider operates an email server of his own to relay your outgoing email. Even if your ISP also uses "anti-spammer" rules, he will accept and relay any email sent from his own customers. You can then modify your Eudora, Outlook, or other email client program configuration to use the ISP's server as your SMTP Server. Leave pangea as your POP Server so you can continue to receive email sent to you at pangea.

If you use a laptop that plugs into the Stanford network and also into a home or other institution network, you can configure your email program to use a special authenticated relay computer maintained by ITSS here at Stanford. This relay will forward all your email, whether you are on or off campus, because it requires authentication first with your SUNet ID and password. Check this ITSS web page for instructions to configure your email client to use this authenticated "smtp-roam" email relay. For this solution, you should use the kerberos authentication method. The SSL authentication method will only work with smtp-roam if your pangea login name is the same as your SUNet ID login name, and you set your pangea local password to be identical to your SUNet ID password, which is not recommended for security reasons.

Another alternative is to use a program that actually runs on pangea to read and send email when you are off campus. No matter where the computer is that you use to connect to pangea, because these programs are actually running on pangea, all mail sent by them originates from pangea itself and will be forwarded anywhere. You can use pangea's webmail program from any web browser, or you can make a command login to pangea and use the pine email program. The PC or Macintosh email client program on your primary office computer must be carefully configured to interoperate correctly with these programs that run directly on pangea.

Finally, if the methods above do not work, it is possible for the pangea system manager to specify particular hostnames, IP addresses, or domains that will be allowed to relay email through pangea. It is important to make these "exceptions" be as specific as possible to limit the ability of email spammers to "sneak in" under the exception. You must contact the pangea system manager to arrange this mail relay exception.

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