Here a new ASP.NET web application created and just one TextBox added on to webform. Now I just run the application with debug mode i.e I hit F5. As a result I got the following error.

"Error while trying to run the project: Unable to debugging on the web server.
Catastrophic failure Would you like to disable future attempts to debug ASP.NET pages for this project?"

If any one knows how to fix please let me know. Either I removed dot net and IIS server and made reinstallation. It is bombing the same error message box

       The error may be either due to the service pack which you have installed or it may be due to the local securities settings.
Before installing the new service pack you could try changing the security settings of the IIS. For that purpose Go to: Control panel ->Administrative tools -> "Local Security Policy" and Click on local Policies, and then on user Rights assignments, Add ASPNET, SERVICE, Administrator as Useres to "impersonate a client after authentication" section. Then restart IIS and try debugging, if its not working further then you have to install the new windows service pack.