First start the Mail program from the Dock at the bottom of the screen.

The following screen appears:

Fill in the fields as shown.

Full Name: Your Name

Your e-mail address: max@mustermann.de

Password: 123456 (was assigned by you when setting up the e-mail mailbox at checkdomain.com).

Then click on "Continue".

You will now see the following screen:

Enter your e-mail login or the complete e-mail address (e.g. info@mustermann.in) as the user name.

Enter the details for the server for incoming e-mails here. If you 

If you want to use the "POP3" protocol, select "POP" as the server type.

If you want to use "IMAP", select "IMAP" accordingly.

Replace all fields with the information about your e-mail box.

You can also find this in your customer login under "E-mails -> Server information".

The program then checks whether the settings 

are correct and logs on to the registered server as a test.

If you get an error message, check the entered values again.

You will see the following screen:

If you do not use SSL, you do not need to check this box.

Click on "Continue".

You will now see the following screen:

Here you enter the server for outgoing mails.

In the field "Description" you can enter any name for the outgoing server.

Fill in the other fields as shown.

Replace all fields with the information for your e-mail box.

You can also find this in your customer login under "E-mails -> Server information".

Enter your e-mail login or the complete e-mail address (e.g. info@mustermann.in) as the user name.

Click on "Continue" if you have entered all the information correctly.

The program then checks again whether the settings are correct and displays the following message 

on the registered server as a test.

If an error message appears, check the entered values again.

The following screen appears:

If you do not use SSL, you do not need to check this box.

Click on "Continue".

You will see the following screen:

Check the box "Connect account to the Internet" here.

Now click on the "Create" button.

Your new email address in Apple Mail will be created.

Now select "Mail -> Settings" from the menu bar of MacMail.

The following screen will appear, in which you select the "Accounts" tab and choose 

click on your "SMTP server":

Then click on "Edit SMTP server list".

A window opens with the SMTP server settings.

In this window, under "Advanced", set the point before "Use own port" and enter the port "587".

Finally, confirm your entries by clicking on the "OK" button.

Your new e-mail address can immediately be used to send and receive e-mails.