In order to troubleshoot a suspicious network connection, we need to determine if all network related services for this workstation are affected.  If so, then it could be that the connection from this workstation to the network itself is the problem.

If you haven't powered down the computer, shut it down, and make sure the power is off.  Then turn the computer back on.  Sometimes network cards can get out of sorts and need to be completely powered down.  If that fixes it - great!  Otherwise, here are some other ideas.

The network card in the computer and the hub or switch it is connected to may have a link light to indicate that an electrical signal is seen across the wire.  (Some network cards don't have a link light).  If you see link lights on both ends, then it is safe to say that each device (the hub and computer) thinks it sees another device on the other end.

If you don't see link lights, then something may be unplugged or broken.  Consider the path from the computer to the hub.  Usually there is a patch cord that connects the network card in the computer to a jack in the wall (horizontal cabling).  Is it plugged into the correct jack?  It's always a good idea to unseat and reseat the cables when you're trying to verify network connectivity.  You should hear a crisp click when the connector is seated.

Now, is the jack you're plugged into the one that is connected up to the hub?  Maybe someone switched it, or knocked it loose.  Another thing to ask yourself is if this cable looks damaged.  Network cables are not very forgiving if you someone has been running over them with an office chair for the last 5 years.  Also, if they're pulled really tight, the connections can get pulled out in the jack itself.  When in doubt, get a "known working" cable to test out the one you suspect.

After each change, you should test the computer again to see if you have found and fixed the problem.

Now that you have checked the patch cord near the computer, you still have another cable in the network closet to check.  This patch cord usually runs from a "Patch Panel" to the hub/switch.  These don't typically wear out on their own, but can be damaged or stretched.  Also, someone may have been testing something in the closet and forgot to plug you back in.  (You should always start your investigation by making sure the wires are plugged in before replacing hardware).  Again, unseating and reseating the connectors at both ends of the cable, listening for a clean snap each time you push the connector in is a good practice.  Did the lights come on?  If not, try replacing this cable with another "known working" patch cord.

If you have a link light, but your computer still isn't seeing the network, then it could be the port on the hub that has gone out (try another one) or the network card in the computer is dead.  You should try powering down your computer completely again.

If you see a link light, but none of the programs are working, the problem may be in the network addressing.

Email Jon with your opinion of this Tech Tip ...

Proudly supplying Denver: Tech Support with a heart