When setting up the mail client on Mac OS, you should do the following:

1. Run the program and open the Mail menu → Add account to open the New Account Creation Wizard.

2. Select "Add another ..." and click to continue.

3. The next step, select "Mail Account"

4. In the Add Mail Account window, specify the following account settings: Full name - is the username, еmail address. Specify the full name of your mailbox, including login, "@" icon and your domain

Password. Enter a valid password for your mailbox