Original Source: http://windowsxp.mvps.org/resetfwpol.htm
When you open the Windows Firewall applet (firewall.cpl) in Windows XP Service Pack 2, it may read as For your security, some settings are controlled by Group Policy at the top of the applet. If this happens to a stand-alone system, then you may use the instructions below to reset the firewall Policy settings to defaults.
Note that there are a plethora of Viruses which disable the Windows Firewall settings through Policy / registry settings, even in Windows XP Home Edition. Therefore, it’s a good idea to run a complete Virus scan in your system.
Method 1: For Windows XP Home and Professional Editions
- Click Start, Run and type Regedit.exe
- Navigate to the following location:
HKEY_LOCAL_MACHINE \ SOFTWARE \ Policies \ Microsoft \ WindowsFirewall
- Backup the key and then delete the WindowsFirewall branch.
- Close Regedit.exe and restart Windows.
Method 2: For Windows XP Professional
- Click Start, Run and type Gpedit.msc
- Navigate to the following branch:
Computer Configuration
=> Administrative Templates
==> Network
===> Network Connections
====> Windows Firewall
=====> Standard Profile
- Set the following options to Not Configured (defaults)
- Windows Firewall: Protect all network connections
- Windows Firewall: Do not allow exceptions
- Windows Firewall: Define program exceptions
- Windows Firewall: Allow local program exceptions
- Windows Firewall: Allow remote administration exception
- Windows Firewall: Allow file and printer sharing exception
- Windows Firewall: Allow ICMP exceptions
- Windows Firewall: Allow Remote Desktop exception
- Windows Firewall: Allow UPnP framework exception
- Windows Firewall: Prohibit notifications
- Windows Firewall: Allow logging
- Windows Firewall: Prohibit unicast response to multicast or broadcast requests
- Windows Firewall: Define port exceptions
- Windows Firewall: Allow local port exceptions
- Exit Group Policy editor.