securepop.t-online.de pop3s it seems to work for me for pop3 ssl fetchmail securepop.t-online.de --service pop3s -u marcus -v Enter password for marfcus@securepop.t-online.de: fetchmail: 6.4.22 querying securepop.t-online.de (protocol IMAP) at Sun 19 Dec 2021 11:55:38 AM CET: poll started Trying to connect to 194.25.134.110/995...connected. fetchmail: Server certificate: fetchmail: Issuer Organization: T-Systems International GmbH fetchmail: Issuer CommonName: TeleSec ServerPass Class 2 CA fetchmail: Subject CommonName: securepop.t-online.de fetchmail: Subject Alternative Name: securepop.t-online.de fetchmail: Subject Alternative Name: popmail.t-online.de fetchmail: Subject Alternative Name: pop-mail.t-online.de fetchmail: Subject Alternative Name: secure-pop.t-online.de fetchmail: Subject Alternative Name: multipop.t-online.de fetchmail: Subject Alternative Name: pop.t-online.de fetchmail: securepop.t-online.de key fingerprint: F1:5F:F4:E5:D6:4C:B8:87:6F:9B:CF:00:F7:FE:44:82 fetchmail: SSL/TLS: using protocol TLSv1.2, cipher ECDHE-RSA-AES256-GCM-SHA384, 256/256 secret/processed bits fetchmail: IMAP< +OK T-Online POP3 Server fpopd securepop.t-online.de ready fetchmail: IMAP> A0001 CAPABILITY fetchmail: IMAP< -ERR Unknown command. similar for imaps