- 1). Log in to the computer with the credentials of a Windows XP Administrator account. Click the "Start" button on the desktop taskbar and click "Control Panel." Select "Windows Firewall" in the Control Panel window.
- 2). Click the "Exceptions" tab in the "Windows Firewall" window that appears. Click on the program in the list displayed that you wish to make available through the firewall. If the program is not in the list, click "Add a Program," then click the program in the "Add a Program" window and click "OK."
- 3). Click the "Change Scope" button, then click the "Custom list" radio button. Type the IP address of the computer you wish to allow access and click "OK."
- 4). Click "OK" in the "Windows Firewall" window to complete the changes.
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