Windows Firewall error settings
The error I was getting: Due to an unidentified problem, Windows cannot display Windows Firewall settings.
I found the solution at:
http://windowsxp.mvps.org/sharedaccess.htm
When you open Services.msc applet, the Windows Firewall/Internet Connection Sharing (ICS) service may not be available in the listing
Windows Firewall/Internet Connection Sharing (ICS) service is available in Services listing, but you are unable to start the service
You receive the following error message while accessing the firewall settings (firewall.cpl)
Due to an unidentified problem, Windows cannot display Windows Firewall settings.
This happens due to missing or corrupt SharedAccess reg key, which represents the Windows Firewall Service.
Download sharedaccess.reg (only for systems running Windows XP Service Pack 2) and save to Desktop. Then double-click the file to merge the contents to the registry. The Services entry will be created. Restart Windows (mandatory step, otherwise the following NETSH command will display an error message).
After restarting Windows, run this from Command Prompt (cmd.exe)
NETSH FIREWALL RESET
Launch firewall applet from Control Panel, and then configure your Windows Firewall settings.
If nothing helps, as a last-resort solution (before reinstalling Windows XP Service Pack 2), give these two commands a try. Click Start, Run and type:
rundll32 setupapi,InstallHinfSection Ndi-Steelhead 132 %windir%\inf\netrass.inf
Restart Windows, and then run this command (from Command Prompt):
NETSH FIREWALL RESET
Attempt to start Firewall applet. Start the Windows Firewall service if prompted.
In case the above site is not longer available I have the file available here - sharedaccess.reg