A common mistake by Admins is use their Hotmail or Gmail as Admin accounts for sending emails from. There are plenty of host providers that will not allow such emails to pass as they will be considered spam or phishing emails.
To solve this problem, there are two solutions:
- Talk your Host Provider to allow email having from your gmail to pass
- Create an email that belongs to your website like firstname.lastname@example.org and link it as your admin account, as some host providers say clearly to register your email IDs used in non-smtp mails through cpanel plugin. Unregistered email IDs will not be allowed in non-smtp emails sent through scripts. Go to Mail section and find “Registered Mail IDs”