---
title: SSL Certificate Installation – Macintosh OS X and Mail
description: "#### Summary You need to install the K12USA Root CA certificate to use the Mail program for Macintosh OS X. #### More Information 1. [Click here](https://ww1.k12usa.com/k12ca.crt) to download the K12USA Root CA Certificate from our servers. 2. Double-click on the…"
url: "https://www.k12usa.com/docs/ssl-certificate-installation-macintosh-os-x-and-mail/"
updated: "2025-11-21"
category: WebMailPRO
tags:
  - WebMailPRO
---

# SSL Certificate Installation – Macintosh OS X and Mail

#### Summary

You need to install the K12USA Root CA certificate to use the Mail program for Macintosh OS X.

#### More Information

1. [Click here](https://ww1.k12usa.com/k12ca.crt) to download the K12USA Root CA Certificate from our servers.
2. Double-click on the Certificate.
    In the box that appears, select **X509 Anchors** from the Keychain list.
    Click the OK button.
   ![](https://www.k12usa.com/wp-content/uploads/2025/11/cert_mac_1.jpg)
3. View the attributes of the keychain after it has been installed, and make sure that the **Always Trust** option is chosen in the drop-down.
   ![](https://www.k12usa.com/wp-content/uploads/2025/11/cert_mac_2.jpg)
4. This is how the account information should look for a k12usa POP3 access account in the Mail program.
   ![](https://www.k12usa.com/wp-content/uploads/2025/11/cert_mac_3.jpg)
5. This is how the Server settings should look.
   ![](https://www.k12usa.com/wp-content/uploads/2025/11/cert_mac_4.jpg)
6. This is how the advanced settings should look.
   ![](https://www.k12usa.com/wp-content/uploads/2025/11/cert_mac_5.jpg)

Once this is done, the security warnings that happen when you connect to the POP3 & SMTP servers over SSL will go away.