This issue occurs because IIS Manager performs a lookup operation to look for a friendly name of the certificate during the installation.
Windows does not allow .well-known folder. It is possible to FTP into your website and create the folder. You can also create the folder using the terminal mkdir command on windows.
In brief the attack could potentially allow the connection to be downgraded to 512-bit which is crackable. Browser vendors are deploying updates to prevent downgrades beyond 1024-bit.
This error occurs when you try to paste your CSR request into the enrolment form.
The Intermediate CA has not been installed. You need to install the relevant Intermediate CA.
This indicates the site is using a outdated security. You can check your SSL certificate using the SSL Labs Checker.
Error produced by Firefox when visiting website secured by a no longer trusted certificate.
This error usually occurs because the website content contains both secure and insecure content. To resolve this issue make sure that the page code does not pull data directly from a non-secure URL.
Google Webmaster Tools has started sending out warnings when it detects a problem with any SSL certificate on your domain.
This error occurs when the CSR request has been generated using IIS7