In order to set up your emails on Mail on macOS follow the guide below:
- Quit macOS Mail if it is open
- Click on the Apple icon in the top left of your screen, then select System Preferences
- Click Internet Accounts
- Add a new account, select Other and then Mail
- Type in your username (email address) and password and click Next
- Mail will likely say the server cannot be found. Enter your domain name prefixed with mail (e.g; mail.customerdomain.co.uk)
