macOS Sierra Mail
While it's still not nearly as easy as the auto-configuration of Thunderbird and other email clients, the process to set up email in macOS Sierra has been greatly streamlined in this version.
Open Apple Mail and if you're not prompted to add an email client pull down Mail->Accounts from the top menu and press the + button for an Email Account.
Select "Other email Account"
Type your name as you'd like it to appear in your From email, your email address hosted at iThinc,
Enter Email Settings Specifics. At this point Mail will popup with a message reading that some information is needed to connect. Your email settings will be:
- Email address: Should be auto-populated from the previous prompt.
- User Name: Copy and paste your email address to this field.
- Password: If this is blank, type your password here
- Account Type: IMAP
- Incoming Mail Server: mail.ithinc.net
- Outgoing Mail Server: mail.ithinc.net
Press the Sign In button at the bottom right and everything should be configured properly.