After pressing [Email] button, you can configure and send email to selected customers. You can specify the SMTP server and port number.
You need to specify the Sender email address. You can try to send an email to yourselves first to test if the mail can be sent successfully. After that, you can hold Ctrl-key to select several customers in the main window and press [Email] button to broadcast an email to all selected customers. This software will send the email one by one so that the customer information will not be shown to others.
If the Message Content contains some HTML tags format, you can check HTML format. Beside Setting field, there are three buttons to add, delete and edit a setting. You can preset some message contents from the setting and select them in future.