Error : “Unable to start debugging on the web server…” ASP.NET 4.0

Question

I am getting an error when I want to create a web site on IIS server. I am using Windows 7 and Visual Studio 2010.

Do I have to register or configure asp.net 4.0 for th

Answer 1

I spent a few hours fighting with this issue. In the end it seems to be that some changes made outside VisualStudio had confused it. I don't know what the issue actually was but things started to work again when I opened a different version from the same solution so that VisualStudio (or IIS) did some magic on the IIS configuration. Then I changed back to the original solution, the configuration was again modified - and now debugging works again.