Cable modem, Router, Desktop and now Laptop

Are you sure it's a router that's connected to the cablemodem? If it's a switch or a hub... or if you're calling the cablemodem itself a router... then we have an entirely different situation here. I bring this up because you mention a specific make and model for the computer, which probably won't be the least bit relevant, but you don't mention the make or model number of what you call the router, and you don't even mention the cablemodem.

Such inconsistency in details raise big red flags because that says to me that no or little attention was paid to the parts that weren't described in detail, and that raises the probability that the problem will be found where little or not attention was paid.

If only one cable works, then the other one is defective. If only one computer works at a time, using either cable, then there's likely a configuration issue, perhaps duplicate computer names or IP addresses, if static addresses are used. Without more details, it's hard to provide more advice.

No, she definetely has both a cable modem and a Router. I do not know the name but it is of recent origin.

The output from the Cable modem goes >> My daughter is using MYACTV in MD. and has all things working as far as

Does the LED for both ports light up on the router? Is the OS configured to use TCP/IP? Is the laptop a "work" unit? It may be configured to use a proxy server that isn't available from home (unless using VPN).....

Makes sense!

Buy another cat 5 wire. Leave the old cat 5 hooked to the PC. Hook the new wire to the laptop. The old wire is hunting for the address of the PC NIC not the laptop NIC. This is a simple issue made complicated by semantics. The best bet would be to get a _knowledgable_ friend to help out.