Setup email account in Apple Mail

Select account type

Select Add Other Mail Account... and click Continue.

Provide personal informations

Enter your name, email address and password, then click Create.

A message Account must be manually configured will appear. Continue by clicking Next.

Enter server settings for incoming emails

Enter imap.nine.ch as "Mail Server", then your complete email address as username as well as your password and click Next.

Providing settings for outgoing emails

Enter smtp.nine.ch as SMTP Server, your complete email address as username and your password. Click Create to complete the account setup.