If '''Emails are not sending''' please check 1. Check if you outgoing E-mail is working by clicking on "Send Test Email". 2. Check your "Descriptive Sending Email Address", it cannot be a word only. The pop up help for the setting has examples of valid formats.
'''If E-mail are sending but guests do not receive your E-mails''' 1. Check if you outgoing E-mail is working by clicking on "Send Test Email". 2. If you see no errors you can use a tool like https://www.mail-tester.com/ to check what the problem might be.