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NIC with only one green light

VJeanne asked
I have one Windows XP system out of 5 that is not connecting to the network. All connected to the same modem. I tested the cables and then switched it out with another systems connection and it still will not connect.

Near the where you put the cable in to the NIC are normal two green lights. What does only one green light at the top mean? I have a few other systems all working and their NIC cards have two green lights.

Could the NIC be bad or could it be something else that I did not think of? Should I try reinstalling it.
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try deleting and reistalling the bad nic. If possible try installing a second network adapter in that machine as well. The lights mean different things on different network adapters. You should have a close look inside the nic on that mahchine and be sure none of hte contacts are bent or stuck.

Have you tried plugging a known good cable into another port that is also known good?  If so, it sounds like you covered all of the hardware basics.  Some more troubleshooting:
1. Update the NIC's driver.  What model NIC is it?  Is it integrated or an add in card?
2. Verify that the NIC is enabled in the Windows Device Manager (Right-click My computer->Manage->Device manager-right-click on the NIC->Properties).
3. Check the Windows Event Logs for NIC specific messages.
4. Try another NIC!


I did plug a know good cable into it.
It is integrated into the mother board.
I am not on site right now. I am going to go there in just a bit and I will do 2 and 3.
I looked for  a new NIC card over the weekend but did not locate one yet.. I will see if I can get one today.

I await the results of 2-4!  As to #1, did you take the good cable and plug it into another modem/switch port (that another PC was using)?
Turns out this issue was from some software that had been removed a few months ago called Pear Echo. When the virus software was updated last Friday it removed a file associated with Pearl Echo that then shut down the network access. Not nice at all. Only after I installed a new USB NIC did I deceide it was not the NIC that was the problem.