WebMatrix forgot my WordPress site

I am preparing my WordPress site with Microsoft Webmatrix. Before I could open my website easily in ‘My Sites’ in Webmatrix, however, it’s not there anymore. However, if I go to My Documents > My Websites, my website folder with all the files and subfolders is still there (WordPress subfolders like wp-admin…).

I also still know the localhost address, but since I can not open my website in WebMatrix I can also not open that address in my browser. How to open my website again in WebMatrix?

Thanks in advance.