The web server is not configured correctly You can configure Visual Studio to always run as an Administrator by right-clicking the Visual Studio shortcut icon, choosing Properties > Advanced, and then choosing to always run as an Administrator. (Some ASP.NET debugging scenarios require elevated privileges.) Restart Visual Studio as an Administrator and retry debugging. IIS does not list a website that matches the launch url Running the webpage outside of the debugger may provide further information.
Often, this error occurs because an error or configuration change has occurred that requires an update to your Application Pools, an IIS reset, or both. When you try to debug an ASP.NET application running on a Web server, you may get this error message: Unable to start debugging on the Web server. Error: Unable to Start Debugging on the Web Server