This usually means the implementation of SSL on your server is not correct. The error is usually caused by a server side problem which the server administrator will need to investigate.
A warning is displayed in the Chrome console window regarding your certificate
This message is sometimes displayed when accessing an SSL page via a proxy (including our own payment page PayPal).
This indicates that the certificate needs to be reissued. This is a result of the Browser distrust.
This means when you generated your CSR request you did not specify the correct 2 digit country code.
The only solution is to re-issue your SSL certificate. Your new certificate will be truncated to 39 months and any remaining months will be lost.
When access a site you may get the above error in Chrome. This is a client side error.
This error occurs when the website has not enabled SSL connections or has blocked port 443.
This occurs when Exchange uses WinHTTP to manage all HTTP and HTTPS connections. You may have configured a proxy in the browser but this is not used by WinHTTP.
The Intermediate CA has not been installed. You need to install the relevant Intermediate CA.