IIS website http ok but https cannot find resource (status code 404)
Solution 1:
It was a corrupt SSL certificate. Knew it could happen but no idea what it looked like.
- Exported the certificate
- Deleted the installed one
- Imported the export
- Edited the 443 Binding on the website to select the new import
- Stopped the site and started.
- Site up and running again.
(reminder to always take an export backup immediately after installation)