The page requires a client certificate

The page you are attempting to access requires your browser to have a Secure Sockets Layer (SSL) client certificate that the Web server will recognize. The client certificate is used for identifying you as a valid user of the resource.

Please try the following:

Contact the Web site administrator if you believe you should be able to view this directory or page without a client certificate, or to obtain a client certificate.

If you already have a client certificate, use your Web browser's security features to ensure that your client certificate is installed properly. (Some Web browsers refer to client certificates as browser or personal certificates.)

HTTP Error 403.7 - Forbidden: SSL client certificate is required.
Internet Information Services (IIS)

Technical Information (for support personnel)

Go to Microsoft Product Support Services and perform a title search for the words HTTP and 403.

Open IIS Help, which is accessible in IIS Manager (inetmgr), and search for topics titled About Certificates, Using Certificate Trust Lists, Enabling Client Certificates, and About Custom Error Messages.