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If I unplug a internet cable from another PC and plug it in my laptop, but it says no internet connection. Then I've been told that the network restrict certain MAC address. My question is that is there any way that I can check if a network is restricting MAC address?

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Change your mac on your laptop to resemble that of your PC and if it allows you to connect you know this is the case. If not then you have a laptop/internet connectivity problem. – Chris Sep 6 '10 at 15:02
Your question has many answers to what people (and I) assume is the actual problem which you are trying to solve. It has none which answers the actual asked question. When you next revisit this site could you please edit your question and add more details. – Hennes Sep 1 '15 at 8:08

You'll probably have to call your Internet service provider and ask. Just keep in mind that MAC addresses can be changed and that there are routers which can give another computer's MAC address to modems connected to them.

Hopefully, someone will be able to provide a more elegant solution.

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How is this an answer to the question - is that is there any way that I can check if a network is restricting MAC address? – Prasanna Sep 1 '15 at 7:35
@Prasanna As far as I am aware, there is no way to actually check. I'm pretty sure that there is no way for a network to actually signalize to end user that he's been rejected due to a black-listed MAC address. So the answer is no and this provides a work-around. Why? Because the usual ways that a black-listed MAC address behaves is very similar to a number of other networking issues. – AndrejaKo Sep 1 '15 at 8:36

It may simply be that the ISP will only allow one DHCP lease on your connection. You don't mention what OS the working PC is running.
Assuming it's Windows go in to cmd (as Administrator if Windows with UAC) and then type ipconfig /release. Then unplug the cable and try on the other machine.

If this works then the simplest and most elegant solution is to use any kind of 'cable' router. They are very cheap now.

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I experienced something similar when I switched my cable modem from one computer to another. It just would not allow the second computer to work. The only workaround was to power cycle the cable modem when switching it between computers.

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This is a common setting on Cable modems. Putting a switch or a router between your computer and your cable modem will resolve the issue as the router/switch is designed to accept multiple devices, while the modem prefers to work with a single device. – music2myear Apr 22 '11 at 18:58

Does your network only consist of one modem and one computer at any given time? For instance, the cable comes out of the wall and goes into a modem, and then a network cable comes out of the modem and goes into your computer or your laptop depending on what you're using at the time?

If so, you should purchase a router. You can get one relatively cheaply: wireless routers will start around $50.

If there is already a router or a switch between the computer and the modem, it may be a MAC address filter. However, generally speaking MAC address filters are only used on wireless networks, due to their being "easier" to connect to than the wired portion of the network or just more public.

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This is not an answer to the question above – Prasanna Sep 1 '15 at 7:25

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