I recently had a nasty issue getting Windows Authentication to work on a local instance of IIS 7.5 (Windows 7 Pro) to an ASP.net 4.0 site. I followed the basic steps.
IIS Authentication
- Disable Anonymous Authentication
- Enable Windows Authentication
Edit web.config
<authentication mode="Windows" />
This did a nice job of enabling Windows Authentication but every attempt to login was rejected and ultimately returned a 401.1 error. This is where the problem started. There appear to be many reasons for this that are well documented around the web including here on Stack Overflow.
I'd tried:
- Editing IIS Authentication 'Advanced settings' for Windows Authentication to disable Extended Protection and Kernel-mode authentication
- Editing IIS Authentication 'Providers' to move NTLM above Negotiate.
- Editing IIS .NET Authorization Rules to explicity Allow users (and various other combinations).
- Various IIS command line scripts and tweaks.
- Various config tweaks in web.config file.
- Even some file system permissions tweaks.
But all to no avail, the dreaded 401.1 remained.
This really is a case of "can't see the wood for the trees". None of the solutions I managed to find (call it a case of bad search parameters if you will) worked for me so I thought it worth posting this question to, hopefully, provide a clear answer that's easier to find for anyone suffering the same issue.