The following instructions will guide you through the SSL installation process on Microsoft IIS 5 & 6
Make sure you have all the following files saved before proceeding:
Your Server Certificate - This is the certificate you received from the CA for your domain. You may have been sent this via email. If not, you can download it by visiting your Account Dashboard and clicking on your order.
Intermediate Certificates - These files allow the devices connecting to your server to identify the issuing CA. There may be more than one of these certificates. If you got your certificate in a ZIP folder, it should also contain the Intermediate certificate(s), which is sometimes referred to as a CA Bundle. If not, download the appropriate CA Bundle for your certificate.
Your Private Key - This file should be on your server, or in your possession if you generated your CSR from a free generator tool. On certain platforms, such as Microsoft IIS, the private key is not immediately visible to you but the server is keeping track of it.
Click Start, Control Panel, Administrative Tools, and then select Internet Information Services (IIS) Manager.
In the left menu, click + next to your local computer and then Web Sites.
Right-click the website (i.e. Default Web Site) that you want to protect and click Properties.
5. In the Default Web Site Properties window, select the Directory Security tab, click Server Certificate…, and then Next.
6. Select Process the pending request and install the certificate and then click Next.
7. Click Browse and locate Your Server Certificate (.crt or .cer) that you previously saved on your server desktop.
Note: In the Open window, select "All files (*.*) for Files of type. This will help when searching for the .crt or .cer file.
8. Click Next, Next, and Finish to complete the installation process.
Congratulations! You've successfully installed your SSL certificate! To check your work, visit the website in your browser at https://yourdomain.tld and view the certificate/site information to see if HTTPS/SSL is working properly. Remember, you may need to restart your server for changes to take effect.
Log into your Sectigo account
Click on the Provide CSR on our website and paste the entire CSR into the blank text box and continue with completing the generation process