# Email not sending

By default, WordPress uses the PHP mail function to send emails generated by WordPress. The most common reason for not sending emails is that your WordPress hosting server is not configured to use [PHP mail()](https://www.php.net/manual/en/function.mail.php) function.

In addition to this, sometimes email providers will flag or block emails that arrive from a different domain than they claim. For example, if your From Email is @gmail.com, but your domain is [www.example.com](http://www.example.com), this domain mismatch may cause an email provider to block the email. Before troubleshooting the issue on server side make sure that contact forms are properly configured:

* When a Default contact form is enabled and the form is not submitted, make sure that you filled out all necessary fields including Email, Subject, and Button text:

{% embed url="<https://docs.stylemixthemes.com/cost-calculator-builder/pro-plugin-features/send-form#default-form-of-cost-calculator-plugin>" %}

* When Contact form 7 is used to send emails, make sure that Mail tab of the Contact form is filled out:

{% embed url="<https://docs.stylemixthemes.com/cost-calculator-builder/pro-plugin-features/send-form/contact-form-7-plugin>" %}

To resolve email delivery issues, we recommend using SMTP to send emails in WordPress. Unlike the PHP mail function, SMTP increases email deliverability by using proper authentication.

For more details as well as setup instructions, please follow our guide for SMTP configuration:

{% embed url="<https://docs.stylemixthemes.com/f-a-q/smtp-settings>" %}


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