A user receives a "Service Unavailable" error message when the user browses your Web site that is hosted on IIS 6.0

When a user browses your Web site that is hosted on Microsoft Internet Information Services (IIS) 6.0, the user may receive an error message that is similar to the following:When you view the System log, you may see a message that is similar to one or both of the following when the rapid-fail protection feature is turned on:

Message 1

Source: W3SVC Event ID: 1011 A process serving application pool 'DefaultAppPool' suffered a fatal communication error with the World Wide Web Publishing Service. The process id was '5684'. The data field contains the error number. Error number: 8007006d

Message 2

Source: W3SVC Event ID: 1002 Application pool 'DefaultAppPool' is being automatically disabled due to a series of failures in the process(es) serving that application pool.

When you view the Http.sys error log, you may see a message that is similar to the following: This issue occurs when IIS 6.0 is running on a Microsoft Windows Server 2003-based domain controller.

This issue may occur if the NT AUTHORITY\NETWORK SERVICE account does not have the permissions to the required registry keys.

To resolve this issue, set the permissions to the required registry keys, and then restart IIS 6.0. To do this, follow these steps:

1. Identify any required registry keys that do not have sufficient permissions. To do this, you can use a tool such as Sysinternals Regmon. For more information about Regmon, visit the following Sysinternals Web site:
   http://technet.microsoft.com/en-us/sysinternals/default.aspx (http://technet.microsoft.com/en-us/sysinternals/default.aspx)
2. Click Start, click Run, type regedit, and then click OK.
3. Set the permissions to each registry key that you identified in step 1. To do this, follow these steps for each registry key:
   1. Right-click the registry key, and then click Permissions.
   2. Click Add, type NETWORK SERVICE, and then click OK.
   3. Click NETWORK SERVICE, click to select the Full Control check box, and then click OK.
4. Quit Registry Editor.
5. Click Start, click Run, type %SystemRoot%\system32\inetsrv\iis.msc, and then click OK.
6. Right-click the server that is running IIS 6.0, click All Tasks, and then click Restart IIS.