What else could be the cause of ';LAN connection 2. A network cable is unplugged'; error message?

The cable is plugged from the router to the computer, I am still unable to connect to the internet with the above message and a red X indicator at the bottom right of the screen. When I plug the same cable from the same router to my other computer, it connects fine to the internet. My Dell Dimenson 4700 desktop only has one port for LAN. My theory is that it has to be the port inside the computer, but I don't know how to be sure of that or how to go about fixing that, if it is the case. Please help.What else could be the cause of ';LAN connection 2. A network cable is unplugged'; error message?
Well due to your description, it sounds like you are running Windows XP. Assuming that I'm right, one issue could be that you don't have the proper drivers. Using whatever computer that you are on the internet with, go to the Dell.com website and look up the Dimension 4700 drivers (use a jump dive, CD, or other storage device to transfer the driver file). Windows XP has issues with plug and play, so that could be it.

If that doesn't fix your problem, check your OTHER router. There is one in my house inside a panel within the master bedroom closet, and basically what it does is it has one Input/Output connection from the ISP and other cables linked to the Ethernet jacks in the wall. NOTE: If you have Vonage, Dial-Up, and maybe (idk) Fiber-to-the-home, you will NOT have one of these.

If that doesn't work, message me. I hope I helped.