The DESY Mailserver
You can access your e-mail via SSL-encrypted IMAP on the mailserver imap.desy.de – this should also work from outside the DESY network. Check the registry to make sure that incoming mail is delivered to the physical address username@mail.desy.de (under “Modify Person”). The server smtp.desy.de is used for outgoing mail – have a look at some information about the configuration of mail programs for more details. A webmail interface is available only for mails which are delivered to win.desy.de.
Be aware that the transmission of outgoing mail is restricted if you are not within the DESY network. If you want to sent DESY emails from outside the DESY network, you have to configure authenticated SMTP. (Note that you need a Windows account to use authenticated SMTP – but you should have one by default, even if you have never made use of it.)