Have you ever come across a situation where you want to access another computer via its UNC (\\computer-name\share) and came across a "Network Path not found" error? Although not too uncommon, this errors can puzzle you in cases where you know all the services required for file sharing are running. I faced this issue the other day and finally after a bit of tussle, I managed to solve the problem. We were trying to access a computer at one of our remote locations and it was giving this error. What made this even more puzzling was that local users were able to access the same computer by using the UNC path. We tried all we could and knew but still the error was the same.
Then I searched on the internet and found some references and a very useful knowledge base article (KB article number 840634) on Microsoft support website which addressed this issue. Apparently somebody had enabled the firewall and the firewall is designed to block File and Printer Sharing from any network and allow access only in the same subnet in its default configuration.
To allow file and print sharing on your computers from any network, follow the steps described below:
- Click on Start --> Settings --> Control Panel. If you are using the Windows XP Start Menu, you can find the Control Panel on the right side of the start menu.
- Category view: In the category view, click on the Security center and then click on Windows Firewall to open the Windows Firewall configuration window. In the Classic view, you will see the Windows Firewall icon.
- Ensure that the Do not Allow Exceptions check box is not checked on the General tab
- Click on Exceptions tab and highlight File and Printer Sharing and click on Edit...to modify the settings. The file and printer sharing is done through port number 445.
- Highlight the TCP 445 and click on Change scope... or just double click to edit it. In the resulting screen, select whether you want to enable for any network for just your network or for a custom list of networks. In case you choose custom list of networks, you will have to manually enter each subnet you want to enable for it to work.
- Click OK your way out and now you should be able to access the computer(s) over the network using UNC path.
A word of caution: I don't recommend setting the scope to Any as is shown here. It means that anyone who can reach your network will be able to access the computer over the network. Either select just the subnet you are on or explicitly define the subnets that you know and trust that would be required to connect remotely using UNC path.