Article ID: 306165 - Last Review: March 29, 2007 - Revision: 3.7

PRB: "Unable to start debugging on the Web server" error message when you debug ASP.NET applications

View products that this article applies to.

This article was previously published under Q306165

SYMPTOMS

When you debug an ASP.NET application in Visual Studio .NET, you may receive the following error message:

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

In Visual Studio 2005 .NET, you receive the following error message:

Unable to start debugging on the web server. An authentication error occurred while communicating with the web server. Please see Help for assistance.

Back to the top

CAUSE

This error occurs because Microsoft Internet Information Server (IIS) is not running or is not functioning properly.

Back to the top

To resolve this problem, you must restart IIS. To do this, type iisreset at a command prompt.

Make sure that the IIS application is configured to use Integrated authentication so it will pass your credentials that are needed to launch the debugger. The anonymous account does not have sufficient permissions to perform debugging.

Back to the top

REFERENCES

For more general information about ASP.NET, refer to the following MSDN newsgroup:

microsoft.public.dotnet.framework.aspnet (http://msdn.microsoft.com/newsgroups/default.aspx?query=microsoft.public.dotnet.framework.aspnet&dg=&cat=en-us-msdn&lang=en&cr=US&pt=&catlist=774F24A2-F71F-425F-AC2B-DC48AB0DA5C9&dglist=&ptlist=&exp=&sloc=en-us)

Back to the top