HTTP Error 401.1 Unauthorized Access is denied due to invalid credentials

In IIS 6, when you configure the applications to work with integrated windows authentication, sometimes you get the following error:

HTTP Error 401.1 Unauthorized Access is denied due to invalid credentials

In order to solve this issue, proceed with the following:

  • run cmd
  • go to: C:\Inetpub\Adminscripts
  • Check if NtAuthenticationProviders metabase property is set to NTLM
  • Type: “cscript adsutil.vbs get w3svc/NTAuthenticationProviders” & enter
  • If you get the message: “The parameter “ntauthenticationproviders” is not set at this node.” proceed
  • Type: cscript adsutil.vbs set w3svc/NTAuthenticationProviders “NTLM” & enter
  • A sample from a machine – click for larger
HTTP Error 401.1 Unauthorized Access
HTTP Error 401.1 Unauthorized Access