If this is a laptop, it most likely has a switch to disable all wireless communication so that you can use it in a plane.

>Hi,
>
>I was using my PC earlier today on a wireless network (at home) without any problems. I came in the office and plug in my cat5 cable but the network icon says unplugged. I tested the network cable on another computer in the office (on which I am typing now) and it works. But when I plug it into my " other" pc it does not work. In the Control Panel -> Networking, the network card does not seem to have any problems. That is, it says, "working properly"
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>What else can I do to troubleshoot this issue? Maybe related or maybe unrelated, also this morning the cordless keyboard does not communicate with the computer.
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>TIA for any suggestions.