"HTTP Error 401.1 - Unauthorized: Access is denied due to invalid credentials" error message w (4333523)

While trying to access the Archive Manager website from the IIS server that serves the Archive Manager site and using the FQDN (Fully Qualified Domain Name) i.e. archivemanager.yourdomain.com the following error is displayed:

HTTP Error 401.1 - Unauthorized: Access is denied due to invalid credentials

This error does not occur ifthe Archive Manager site is accessed using the FQDN from any machine other than the Archive Manager IIS server.

This issue occurs if Microsoft Windows XP Service Pack 2 (SP2) or Microsoft Windows Server 2003 Service Pack 1 (SP1) is installed.

Windows XP SP2 and Windows Server 2003 SP1 include a loopback check security feature that is designed to help prevent reflection attacks on the computer. Therefore, authentication fails if the FQDN or the custom host header that is used does not match the local computer name.

This applies to Microsoft Internet Information Services 7.0, when used with:

• Windows Server 2008 Standard/Enterprise/Datacenter
• Windows Server 2008 R2 Standard/Enterprise

Download and run this MS "Fix It" on the Archive Manager server: http://go.microsoft.com/?linkid=9686309 .

For more information or to make the change manually, visit http://support.microsoft.com/kb/896861

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