You will need
  • The computer network cable.
The most common reason that the computer does not see the network cable, are the mechanical damage of the cable. To start, try to disconnect the cable from the port of the network device and turn on again. If the problem persists, disconnect again and inspect the connectors on the cable ends. Cracks and damage should not be. If found damaged, need to replace the connectors using a special crimping device. It can be bought at any electronics store. If this is difficult contact the professionals.
If the connectors are all right, examine carefully the surface of the cable. Often appear on the braid breaks, intersecting and other damages, as a result, the computer ceases to see a network cable. In this case, the cable must be replaced or "bandage" tape.
If the computer still does not see the network cable, inspect the port. The problem may be in network interface, router, hub or the computer itself. Check the connections for integrity. They should not be bent or damaged. If the port is broken, you can replace them, you need to contact the experts.
After damage is resolved, enable the network device and connect the work cable to it. Indicator should illuminate yellow and green colors. If the glow is absent, then the port is still not receiving signal.
If the cable is intact and external damage on it, you can try to reinstall the network card. Press the key combination Win+R, in the dialog box "run" write devmgmt.msc and click OK. A window should open device Manager and choose "network adapters", then find the controllers - they can be Realtek, Atheros, Intel, Nvidia, and then you have to press "delete". After you restart the computer will find and install the network card driver. If this doesn't help, maybe a broken network card itself. Then you can try to put another ode in the PCI slot, if a set fee is integrated into the motherboard of the computer.
If, during the Internet periodically disappears and the signal no longer to load sites, most likely, the network cable has a hidden defect, even if the light port lights remain lit. If the problem is ongoing, it is recommended to replace the network cable.