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I have a broadband connection from a cat5 cable connects directly to my laptop. It was working perfectly fine till yesterday. Suddenly I can see that when I am connecting the cable to my laptop the lights of the LAN port is not blinking and hence it's showing that the "No network Available, cable is unplugged" in my network status.

Also the weird thing is when I am disconnecting the cable automatically the lights (green and orange) start blinking and in the network status it's showing that "Unidentified network".

  1. I checked the cable connecting a ADSL router and can see that the LAN light is blinking so there is no problem with the cable.
  2. IP configuration is also correct.
  3. In the "device Manager" I can see my LAN card available". It is showing that this device is working properly.
  4. I tried to uninstall and reinstall the LAN card but no luck.

Is this a software issue? If yes, then how can I resolve that? If it's a hardware issue then how I could I identify it?

share|improve this question
Have you tried pushing it gently up and down in the port? Seems like a loose connection maybe there is a problem with the connectors on the computers side? – MrJones2015 Mar 25 '13 at 9:16
Yes I tried pushing it up and down in the port no light is coming up in the ethernet port in laptop but when I am disconnecting it or connecting any other RJ45 jack (whose other side does not connect to anything else) the light is blinking. If its a laptop problem then how do I fix that ? Is it possible to do that ? – Avirup Chatterjee Mar 25 '13 at 9:32
if it's a hardware issue it could be you have identified it! bad RJ45 port or more specifically, the controller which is the thing other than the appearance, about the port. The circuitry. I don't know how common that is. Perhaps you can use PCMCIA or USB, and PCMCIA may be more reliable. (I don't knoe if PCMCIA is still used). I don't know how common a bad RJ45 port ethernet controller is. (obviously if your laptop is under warranty then give them a call + they do tech support to diagnose if it is that - they might think that it is) – barlop Mar 25 '13 at 9:47
You haven't yet tried another cable though. i'd try a bunch of different cables. You may find one cable is for some odd reason very lenient and works in any. I might've seen that once from vga cable and a picky monitor. And i've seen it with ps2-usb adapters(one usb port of one computer is picky, another computer's usb ports are lenient and work with any, one ps2-usb adapter works with any computer, one is picky). (I chucked the picky ps2-usb adapters out!). Was inexplicable but diagnosable. Haven't seen it for anything else eg ethernet. It's unlikely but wouldn't rule it out unless tested. – barlop Mar 25 '13 at 9:50

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