When attempting to install a legacy NE2000-Compatible or 3COM Etherlink III 3C509 network card under
Windows XP, Windows will fail to recognize it exists.

However, there is a very simple trick to "convince" Windows XP to use such network cards.
For that, you need to get an installation-file (INF-file) with the configuration/settings of the network
card. And for Windows XP, the Windows 2000 Prof INF-file will work :
*"netnovel.inf" for installation of a NE2000-Compatible Non-Plug&Play Network adapter
*"netel5x9.inf"for installation of 3COM EtherLink III 3C509 Non-Plug&Play Network adapter
( copied from a Windows 2000 Prof. system)

Before continuing, make sure that you know the IRQ or I/O-range , which is used by your network adapter !

	In the Control-Panel : "Add Hardware" It will first search for some new hardware, but not find any ISA Network card.
	Confirm, that the hardware (the network card) is already installed.
	Since I am not connecting any hardware to a serial port or USB, but a new device, I selected "Add a new hardware device". The next screen (no screen dump) allows to search automatic or to select manual : I tried automatic and nothing was found, so I tried again with manual selection. then select from the list of hardware type : Network Adapters:
	Use now the button "Have Disk..."
	If you have stored the "Netnovel.inf" file on your disk, use "Browse.." to locate the folder containing the INF-file. Then continue with "OK"
	Installing an NE2000 Compatible, using the "netnovel.inf"-file : Locate on the left under "Manufacturer" "Novell/Anthem", then select on the right under "Network Adapter" the "NE2000 Compatible". Installing an Etherlink 3 3COM 3C509, using the "netel5x9.inf"-file : Locate on the left under "Manufacturer" "3com", then select on the right under "Network Adapter" the "Etherlink III (3C509/509B) in Legacy..".
	Select "Next" to install the drivers for this network adapter. surprise : although the INF-files for these network adapters were not included with Windows XP, the drivers are included !
	But these driver have never been tested by Microsoft with Windows XP. (it is not a new Windows XP driver, it is an "old" Windows 2000 driver). To ignore this warning, select to "Continue Anyway"
	The driver is now installed, but since Windows could not detect with such non-Plug&Play devices the hardware configuration of the adapter, you have now to "view or change resource for this hardware" (you can also do that later in the Device Manager)
	Unlike previous versions of Windows (which would use default values), Windows XP does not assign any resources. Select to "Set Configuration Manually"
	No IRQ or I/O-range has been assign. Click on the "IRQ" to select it, then on the button "Change Setting..."
	Change the value to the IRQ used by your network card. If the section "Conflict information" shows a conflict with another device: - if that is also an ISA device (like COM1 or COM2), then you must reconfigure your network adapter to use another IRQ. - if that is a PCI-device, you can continue, because Windows XP will give your request to use the IRQ for this "legacy" device priority and will assign another IRQ to this PCI device.
	Select OK to use the value : if the conflicting device is a PCI device, continue with "Yes"
	Click also on "I/O range", then use "Change Setting.." to assign the proper value. Select "OK" to store the new configuration values. Note : These I/O-Range amd IRQ settings worked for me, because my network cards were configured to use these resources. You need to make sure that you define values matching the configuration of your network card !
	You will be prompted : To be able to use the network adapter, you must reboot !
	After the restart, verify in "Device Manager", that the installation was successful. ( In my example, the "NE2000 Compatible" was installed as second network adapter ) Double-click on the adapter to display the Properties
	tab: General make sure, that it shows : "This device is working properly"
	tab : Driver These drivers are provided by Microsoft, and when looking at the Driver-date : these seem to be the Windows 2000 driver for the NE2000-Compatible and Etherlonk III 3C509..
	tab : Resource The IRQ or I/O-range , as configured during the installation You have here the option to "Change the Settings", but if you decided to change the values for the IRQ or I/O-range here, you must also change the settings on your network card, by either changing the jumper settings or by running the configuration utility of the network card.

Talking about Resource management : During the configuration of my network card, the system had complained about a "resource conflict". lets check now the resource-summary for irq's : select in the menu : view to display the "resource by type" : And select to display the IRQ's : No more conflict, only the NE2000 Compatible is using IRQ 10. (the previous user of IRQ10 has been configure to use now a different IRQ).

When requesting Resource for Legacy devices, like a non-Plug&Play ISA Network card, it is "Forced Hardware" (as shown by "System Information)