Resolving "The remote certificate is invalid according to the validation procedure." Error When Sending Mail

Problem Overview

If you’re encountering the error message “The remote certificate is invalid according to the validation procedure” when attempting to send mail, it typically indicates wrong configuration of the mail client your are using or an issue with the SSL/TLS certificate used by your mail server. This error is often triggered when the mail client cannot validate the server’s certificate due to reasons such as:

• Wrong hostname provided as server name.
• The certificate has expired.
• The certificate is not issued by a trusted certificate authority.
• The certificate does not match the server name.

This error is a security measure to prevent potential man-in-the-middle attacks, where an attacker could intercept the communication between your mail client and the server.

Solution

To resolve this issue, it is recommend to use the mail configuration settings provided in your Site Tools. These settings are specifically designed to work with your mail server and should help you avoid the certificate validation error. Here are the steps to access these settings:

1. Log in to your Site Tools and navigate to the Email -> Accounts section.
2. Find the email account you’re having trouble with and click on the Action menu next to it.
3. In the dropdown menu, select Mail Configuration.
4. Navigate to the Manual Settings tab.

In the Manual Settings tab, you’ll find the correct configuration settings for your mail client, including the server names, port numbers, and encryption methods. Make sure to update these settings in your mail client accordingly.

Remember, these settings are unique to each email account, so ensure you’re using the correct settings for the account you’re having trouble with.