Disable the loopback check

This is used to fix a logon issue with NTLM and IIS, the error message:

Logon Failure:
Reason: An error occurred during logon
User Name: [User Name]
Domain: [Domain]
Logon Type: 3
Logon Process: Èù®
Authentication Package: NTLM
Workstation Name: [Workstation Name]
Status code: 0xC000006D
Substatus code: 0x0
Caller User Name: -
Caller Domain: -
Caller Logon ID: -
Caller Process ID: -
Transited Services: -
Source Network Address: 127.0.0.1
Source Port: 1298


For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

the following steps will fix the issue:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. Right-click Lsa, point to New, and then click DWORD Value.
4. Type DisableLoopbackCheck, and then press ENTER.
5. Right-click DisableLoopbackCheck, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Quit Registry Editor, and then restart your computer.

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