Windows Server 2003 SP1 introduced a loopback security check. This feature is also present in Windows Server 2008 R2.
The feature prevents access to a web application using a fully qualified domain name (FQDN) if an attempt to access it takes place from a machine that hosts that application. The end result is a 401.1 Access Denied from the web server and a logon failure in the event log.
Another problem is that the search crawler failing
Apply the fix mentioned in http://support.microsoft.com/kb/896861 only for DEV environments.
Method 2: Disable the loopback check
To set the DisableLoopbackCheck registry key, follow these steps:
- Click Start, click Run, type regedit, and then click OK.
- In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
- Right-click Lsa, point to New, and then click DWORD Value.
- Type DisableLoopbackCheck, and then press ENTER.
- Right-click DisableLoopbackCheck, and then click Modify.
- In the Value data box, type 1, and then click OK.
- Quit Registry Editor, and then restart your computer.