T-Mobile Online Germany E-mail Settings for iPhone

Incoming (IMAP) Mail Server Configuration

Server Hostname secureimap.t-online.de
Server Port 993
Username The part before the @ sign of your e-mail address
Authentication Password
SSL/TLS Yes

Outgoing Mail Server Configuration

Server Hostname securesmtp.t-online.de
Server Port 465
Username The part before the @ sign of your e-mail address
Authentication Password
SSL/TLS Yes