Article ID: 318465 - View products that this article applies to.
This article was previously published under Q318465
When you debug an ASP.NET application in Microsoft Visual Studio .NET, you may receive the following Microsoft Development Environment error message:
Error while trying to run project: Unable to start debugging on the web server. The server does not support debugging of ASP.NET or ATL Server applications. Run setup to install the Visual Studio .NET server components. If setup has been run, verify that a valid URL has been specified.
You may also want to refer to the ASP.NET and ATL Server debugging topic in the online documentation. Would you like to disable future attempts to debug ASP.NET pages for this project?
This error may occur if the Microsoft .NET Framework setup or installation was not completed correctly. When this occurs, the application mappings for ASP.NET file name extensions (such as .aspx) are not configured correctly in Microsoft Internet Information Services (IIS).
To check whether the application mappings are correct, follow these steps:
To resolve this problem, use the Aspnet_regiis.exe administration utility that manages the installation and uninstallation of multiple versions of ASP.NET on a single computer.
To use the Aspnet_regiis.exe utility, follow these steps:
For additional information about other ASP.NET debugging problems, click the article number below to view the article in the Microsoft Knowledge Base:
306172For a description of symptoms typically related to ASP.NET and IIS application mappings that are not configured properly, see Microsoft Knowledge Base article Q325093.
(https://support.microsoft.com/kb/306172/EN-US/ )INFO: Common Errors When You Debug ASP.NET Applications in Visual Studio .NET
325093For more information about ASP.NET debugging, see the following MSDN Web site:
(https://support.microsoft.com/kb/325093/EN-US/ )PRB: ASP.NET Pages Exhibit Unexpected Behavior Because the Server-Side Code Is Not Processed
Debugging ASP.NET Web Applications
Article ID: 318465 - Last Review: October 16, 2012 - Revision: 5.0