Some Issues of IIS 7.0
ModuleIIS Web Core NotificationBeginRequest HandlerNot yet determined Error Code0x80070021 Config ErrorThis configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault="Deny"), or set explicitly by a location tag with overrideMode="Deny" or the legacy allowOverride="false".
appcmd解决这个问题的command line: appcmd.exe unlock config "web site name" -section:system.webServer/Handler -commitPath:apphost
AppCmd.exe is located in the %systemroot%\system32\inetsrv\ directory. Because it is not path of the PATH automatically, you need to use the full path to the executable when executing commands like in "%systemroot%\system32\inetsrv\AppCmd.exe list sites". Alternatively, you can manually add the inetsrv directory to the path on your machine so that you can access AppCmd.exe directly from any location.