Computer Help, Network Services and Technical Support

If you are constantly getting asked for a username and password - error HTTP
401.1 - Unauthorized: Logon Failed - when trying to administer your Extended
Website on Windows 2003 Server w/IIS 6.0 or 5.1 then you are not alone! It
happens on Websites that use Integrated Authentication.

The behavior is by design and you can always administer from a networked
client. Yes, the admin username and password will work from a networked
client.

The other solution which takes away the intentional MS Security block -
disables the loopback check for host headers matching the machine name - is
to:

Start, Run, Regedit and got to the:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa key.
Right-click Lsa and choose; New; DWord Value
Type in DisableLoopbackCheck and hit Enter
Type in number 1 for the Value Data

Quit Regedit and Reboot your Win XP SP2 or W2003 SP1 computer

for causes and other solutions to match host header to your sites read:

http://support.microsoft.com/kb/896861

Good Luck!

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