403 - Forbidden: Access is denied

I have installed the certificate on Windows 2012R2 and IIS8.5. I used the automated installation from https://github.com/Lone-Coder/letsencrypt-win-simple. Everything went fine with the exception that now I have the website saying: Server error, 403 - Forbidden: Access is denied. The permissions to the website’s folder/files are granted to Everyone with Full access.
Any ideas how to fix this?

Check your bindings. Try enabling SNI. hmm. Yeah probably bindings.

The bindings are there. When I’m browsing the website is working, I have the green lock saying the communication with the website is secure.

Did you ever solve this?

OK I solved it. It was due to the changes I had to make to the handler mappings for the certificate verification. Once I reverted the handler mappings this issue disappeared.

Hi Ryan.
I am having the same problem. I am unaware of the handler mappings for certificate verification. Can you give me some pointers please?