Windows XP Firewall Setup for NLM
The Network License Manager program uses Ethernet communications over networks to receive and send data. It is possible that the Windows XP firewall (or some other firewall) can block communications in one or both directions if the firewall or firewalls do not recognize an application, like NLM, that is trying to communicate through the Ethernet.
To give an application permission to communicate, it is sometimes necessary to enter the program name into an exceptions list in the Windows Firewall dialog. You can find the Windows Firewall icon in the Control Panel. Double click on the icon to load the dialog, then select the Exceptions tab. Search through the list of programs to find "attnlm". If it is not there, then it will need to be added and the check box checked like this:
Client Computer and Program Setup
The same is true on the client computer (the computer with the program that needs to find NLM). That program needs to be entered in the exceptions list if it is not there.
For example, if you are using KeyCheck.exe in the client computer, then it is important that KeyCheck.exe is allowed to receive messages from other computers on the network. Use the same process for adding the exception in the Windows Firewall dialog on every computer and every program that must communicate with NLM through the network or the internet.
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