Some require motherboard drivers. Have you looked for such?
Bob
This one has me scratching my head. I upgraded my OS to XP from win2k on my Compaq from work. It was a 2 year old machine with an corporate image and off the books, so I decided to rid myself of all the unnecessary automated scripts. So now the network shows unplugged, but the madge nic card is working properly. Suspecting some kind of security device which disabled the network connection, I did the following:
1) pulled the nic: uninstalled the driver, reinstalled XP, disabled and re-enabled. Nothing
2) put in another nic card, first in slot 1, then slot 2, then with both nic cards.
3) Device manager shows them working properly
4) Confirmed my cables are working by plugging them into another computer.
Any ideas?

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