Help for when “The website is unable to display the webpage”
This Internet Explorer error message means that IE could connect to the web server, but the web server does not support either
Check the title bar at the top of the Internet Explorer window to determine which of these occurred, and then follow the link in the relevant point above to learn what you can do to fix the error.
Microsoft Knowledge Base article 811262: ““Error Message: Error 501/505: Not Implemented or Not Supported””
Microsoft state in their help with website error messages that:
“These errors might occur if you have HTTP 1.1 enabled. [See instructions for how to stop Internet Explorer using HTTP 1.1] These errors might also occur if a third-party product is interfering with Internet Explorer. Try closing all programs and then attempt to access the webpage again.”