You may receive the error "An authentication error occurred while communicating with the web server. Please see Help for assistance"

When working with Visual Studio 2005 on Windows Vista and create web applications running out of IIS 7, you need to perform a few steps before getting it work.  I had blogged about it, in my earlier post

However, after performing all the above, you might still get "An authentication error occurred while communicating with the web server. Please see Help for assistance" when trying to create a website / debugging a website created using Visual Studio 2005 running on a Windows Vista with IIS 7.

There is a public hot fix available which can be downloaded for FREE.

The Web Dev Tools team put up a nice post on this http://blogs.msdn.com/webdevtools/archive/2007/06/20/downloadable-hotifx-f5-debugging-using-iis-fails-on-vista-home-editions.aspx

Also check http://mvolo.com/blogs/serverside/archive/2006/12/28/Fix-problems-with-Visual-Studio-F5-debugging-of-ASP.NET-applications-on-IIS7-Vista.aspx which provides better explanation with visual steps.

Cheers !!!