| Configure the SharePoint server to ensure SSL Mutual authentication of both client and server during the entire session. |
Open IIS Manager.
In the Connections pane, expand "Sites".
Click the "Web Application" site.
In the Actions pane, click "Bindings".
In the Site Bindings window, click "Add".
In the Add Site Binding window, change "Type" to "https", and select the site's SSL certificate. Click "OK".
Remove all bindings that do not use https.