When you install an SSL onto an Addon Domain in cPanel hosting, it is not an automatic install like it is with the primary domain for the hosting account. You will have to manually setup, create, and install the SSL on the Addon Domain.

Big shout out and THANK YOU to Chris Eggleston who developed the below tutorial for helpful developers, do it yourself types and GoDaddy tech support who provided HIS LINK to begin with!!! GOD BLESS YOU, CHRIS. Saved us. Original post here: https://chriseggleston.com/adding-ssl-addon-domain-cpanel/

Ready to Do-it-Yourself?

In this tutorial you will be managing two different products.

1. The SSL Certificate
2. The cPanel Hosting

This tutorial is done from a GoDaddy account where both the hosting and SSL live. The same steps would apply no matter where your cPanel Hosting and SSL were purchased.

Step 1: Start the setup in cPanel

1. In the search bar type SSL
2. Click on the “SSL/TLS” icon

Once in the SSL/TLS manager, you will have a total of three (3) steps to complete. After completing step 1 below, you will have to switch back over to the SSL Manager. Each of the steps below are outlined in individual screenshots.

Step 1.1: Generating a CSR

1. In the drop down, select Generate New…
2. Enter your domain name you want this SSL to cover
3. Enter the City of business or mailing address
4. Enter the State your business is registered in
5. Chose your Country from the drop down
6. Enter the company name (if no company enter your name)
7. Company division would be your role; i.e Owner, Marketing, IT
8. Enter the best email address for contacting you
9. Click “Generate”

Passphrase and description are optional.

Step 2: Use the CSR to Generate the SSL Cert

After clicking Generate in the previous step, you will see the page as displayed below.

Copy the strange looking text in the gray box

Step 2b: Generating the SSL Certificate

Head back over to the section of your account where you manage your SSLs.

Click “Setup”

After clicking on Setup, you will be presented with the following…

1. Select “Provide a certificate signing request (CSR)”
2. Past that strange looking text (your CSR) in the box
3. Agree to the terms
4. Click “Request Certificate”

After clicking the “Request Certificate” button in the previous step, you will see the screen displayed below.

This means you did it right!

Step 3: Installing your certificate on cPanel

Once the SSL Certificate has completed verification, it will issue a certificate and you will see the screen below.

1. Click “Download”

After clicking download you will be presented with two additional steps.

1. In the drop down, select your “Server Type”. In my case, “Apache”.
2. Click “Download Zip File”

Once the zip file is downloaded to your computer and unzipped, you will have two files.

Very Important => You want to use the file that is a random string of numbers and letters. NOT the one titled gd_bundle-….

Step 3b: Uploading the SSL Cert in cPanel

Once the files are extracted on your machine, head back over to cPanel to the SSL/TLS section and click on the third option, “Certificates (CRT)”. Then follow the steps below.

1. Click on “Choose File”
2. Locate the file on your machine and select it
3. Click on “Open”
4. Click “Upload Certificate”

Step 3b: Installing the SSL Cert in cPanel

For the final step, you have to install the certificate. In the cPanel SSL/TLS section, go down to the last option “Install and Manage SSL”.

1. In the drop down, select your domain
2. Click on “Autofill by Domain” (verify all boxes are populated and hve green check marks)
3. Click “Install Certificate”

When you see the message below, you will know that your SSL is installed and configured properly.

Your site will now resolve to HTTPS and show the green padlock.

Wrap Up and Review

You’ve just learned something not many people know how to do! Hopefully you found it easier then you thought it would be.

If you’ve gotten to this point and your install was not a success or you’re already overwhelmed and this is just too much work, order a One Time Fix and I’ll get it taken care of within 24 hours.

If you’re determined to get this done yourself and have additional questions or concerns, use the comments below and I’ll be happy to help you get things sorted out.