C # IIS Error configuration information (500.19-internal Server error)

This error occurs because IIS 7 employs a more secure Web. config management mechanism, which by default locks the configuration items from being allowed to change.

To unlock can run the command line as an administrator

%windir%\system32\inetsrv\appcmd Unlock Config-section:system.webserver/handlers

Where the handlers is the name of the node in the error message that appears in red letters

If the modules is also locked, it can be run

%windir%\system32\inetsrv\appcmd Unlock Config-section:system.webserver/modules

C # IIS Error configuration information (500.19-internal Server error)