Share Files Freely in Xp

A firewall is a layer of protection for your Internet connection that permits or denies access based on a pre-determined set of rules. Windows XP comes with a built-in firewall feature called the Internet Connection Firewall. However, the default firewall rules will disable access to shared files from other computers on your local network. If you haven't yet enabled the Internet Connection Firewall, here's how you do it:

• Open the Network Connections window (through Control Panel, or right-click on the My Network Places icon and select Properties).
• Right-click the icon corresponding your Internet connection, and select Properties. Choose the Advanced tab, and turn on the Protect my computer and network by limiting or preventing access to this computer from the Internet option, and click OK. (If the option is grayed-out, you've either right-clicked the wrong connection icon, or your Internet connection isn't set up properly.)
• The change will take effect immediately.

Now, here's to adjust Windows XP's Internet Connection Firewall so that it permits access to shared files:

• First, make sure that the firewall is your problem. With the firewall enabled, try accessing a shared folder from another computer. Then, disable the firewall and try again. If disabling the firewall fixes the problem, then proceed with this solution. Otherwise, the problem is not your firewall.
• Open the Network Connections window (through Control Panel, or right-click on the My Network Places icon and select Properties).
• Right-click the icon corresponding your Internet connection, and select Properties.
• Choose the Advanced tab, and click Settings.
• Under the Services tab, click Add.
• Type File Sharing for the description, 127.0.0.1 for the IP address, and 445 for both the external and internal port fields. (127.0.0.1 is the loopback address which refers back to the same computer.)
• Click Ok when you're done, and then place a checkmark next to the newly added service. Click Ok two more times to close the remaining windows; the change will take effect immediately.
• If it still doesn't work, you'll need to return to the Service Settings window, as described above. Repeat steps 5-7 four times to add four additional services. Instead of 445, however, the services will use ports 135, 136, 137, and 138, respectively. Once you get it working, you may wish to experiment by removing the new services, one-by-one, until it stops working again. That way, you can eliminate the open ports you don't need.I am not sure of the exact port number.

It's important to realize that if you enable firewall access through these ports, you're opening them for anyone and everyone. Unfortunately, Windows XP's Internet Connection Firewall is incapable of allowing access to some computers while restricting access for others (you'd need a third-party firewall program for that). If you need to enable access to computers in your local network and disable access to computers elsewhere, you'll need two network connections (and two network adapters): one firewalled Internet connection, and one standard LAN connection.