A mail server test is a process of evaluating the performance and reliability of an email server. The test can be used to check if the server is configured properly and functioning as expected, and to identify any potential issues that may be impacting the delivery of email messages.

Typically, a mail server test will include the following checks:

1. MX record resolution: This checks if the MX (Mail Exchange) record for the domain is properly configured and points to the correct mail server. You may also use our MX Validator tool to verify proper configuration of MX records for the domain name.
2. A record resolution: MX records map a domain name to one or more mail servers, and each mail server is identified by either the A (Address) or CNAME record. The A or CNAME record for the mail server must exist in order for the mail server to work properly.
3. Reverse DNS Lookup: This checks to ensure all your A record for the mail servers have Reverse DNS (PTR) records.
4. SPF Record Lookup: This checks to ensure that your domain name has a SPF Record, which will prevent spammers from abusing your domain name.
5. DMARC Record Lookup: This checks to ensure that your domain name has a DMARC Record, which will protecging your domain from fraudulent emails.
6. Connection to the server: This checks if the server is accessible and accepting connections from client devices.
7. Authentication: This checks if the server requires authentication and if the provided credentials are valid. This is available through our SMTP Test tool.
8. Email delivery: This tests if the server can deliver email messages to a specific recipient email address.
9. Email retrieval: This tests if the server can retrieve email messages from a specific email address. We do not test email retrieval as send test will generally verifies authentication and email functionality.

The results of a mail server test can provide valuable information for troubleshooting and improving the performance of the email system. It can also help ensure that email messages are being delivered and received correctly, which is critical for many businesses and organizations.