If you having this problem of not able to access Microsoft website including their Windows Update site, there is a possibility your PC is infected by conflicker virus. To verify it, go to this website.
There are few conflicker removal tools in the web and you can easily google it. However since conflicker also prevent you from going to some antivirus webpage, you have to use other non-infected PC to download any tools from the antivirus webpage or find a third party webpage that host the conflicker removal tool like this.
