Can iMessages be used on Windows PC?

I wanted to access my iMessages from my computer that runs Windows, but it didn't work. Whenever I try to reload the webpage, it says "You do not seem to have access to this page. Please contact Admin." I don't understand why this is happening because I am the admin on the computer. There is also a small addition to the url that says "/mmuser/#/error?s=unauth" What does this mean and how can I access my iMessages on Windows?

[Re-Titled by Moderator]