Accessing the site from inside the Front End server

I was accessing a site from a client without a problem. Even the authentication whould have pick up the windows credentials and so it would be an automatic login without having to specifically type the credentials. As it should be!

Now, the same site in the server that hosts it would not only asked me authentication but as well would not allow access after credentials have been given.

To solve this, I follow kb896861 from Microsoft:
You receive error 401.1 when you browse a Web site that uses Integrated Authentication and is hosted on IIS 5.1 or IIS 6

Allowing ASP.NET 2.0

If the ASP.NET is not listed in yor web server extensions folder in the IIS, you need to manually install it and enable it. Please follow this steps. Though it is in the documentation of WSS 2.0, it perfectly apply on the WSS 3.0 as well:

Installing and Configuring ASP.NET

Reset IE

If you are experiencing any problems with IE or with sites (when before you didn't have this problem), just reset IE settings. This deletes all the cookies, ActiveX, passwords, browsing history, etc. Actually it turn IE to be what it was when you first turned it on.

Here you find the instructions on how to do this. This was the problem I got when I found it. It was solved by resetting it:
Error message when you check for updates on the Windows Update site: "0X800A138F: There are no updates available at this time"

Last Update: 16.May.2009