Outgoing mail server at a glance
An outgoing mail server sends outgoing emails. Every email provider, including IONOS, has its own servers, the addresses of which must be entered into your email program (e.g. Outlook, Thunderbird, or Apple Mail) in order to send emails.
Emails are sent via the SMTP protocol and received via an incoming mail server.
IONOS’s webmail already uses the correct outgoing mail server, so there is no need to enter an incoming mail server here.
Details about the IONOS outgoing mail server can be found in the article IONOS Mail: Server details for IMAP, POP3, and SMTP.