Local Area Connection doesn't have a valid IP configuration

[TEH2302]

I have two computers side by side plugged into a Netgear wired switch. One computer works, the other does not. The one that does not work works when I hook it directly to the modem though.

When it is hooked to the switch it says "Local Area Connection doesn't have a valid IP configuration" when I troubleshoot it.

Thank you for any help!

 

[AddRAM]

Re boot the modem, reboot the switch. Re boot the problem pc.

There is no reason the second pc shouldn`t work off the switch.

Are you positive it`s a switch ?

 

[TEH2302]

Yes it's a switch

I have rebooted everything and it still does not work.

 

[Ztruker]

Does it work if you connect just that PC to the switch?

 

[TEH2302]

No it does not.

 

[AddRAM]

It sounds like the modem is the problem , it`s not a router so it`s not handing out more then 1 ip address.

This rules out the pc being the problem.

Test each pc 1 at a time, are the ip addresses the same ?

Post the exact make and model of the modem, we can then research.

https://askleo.com/why_does_my_home_network_only_work_with_one_computer_at_a_time/

 

[TEH2302]

I take that back, i tried it again and the computer that doesn't work DOES work on the switch if it's the only one.

Only one can work at a time on the switch.

The one that does not work has an IP address of 169.254.146.179.
From the link above it says "a “169.” is an address that Windows will simply make up in order to have an address – but most things won’t work."

DHCP is enabled.

How do I fix this?

 

[doctore]

Post a screen of your router's DHCP settings, would you?

 

[AddRAM]

doctore, he says he has a modem, he does not say he has a router, there in lies the problem.

Still waiting on the make and model of the modem.

The modem connects to a cable/wire from the outside, bringing in Internet data (email, You Tube videos, Google search results, files) from all over the world. A different wire that goes from your modem to your computer delivers your Internet requests and activity to your computer and monitor. What you see is what you asked for. Thanks, modem!

In case you're wondering, you can't simply plug that cable from your Internet Service Provider directly into your computer. It just doesn't work that way. You NEED that modem between the cable and your computer. No modem, no Internet.

You could go online using just your modem and computer, but there's a reason to think twice. Modems are useful, but they are not smart pieces of hardware. They can't do much when it comes to providing Internet safety, like keeping hackers away. Also, one modem connects to only one computer.

So with just a modem, your computer is at risk. You'll need to rely on special computer software (anti-virus programs, etc.) to fight of bad stuff coming in from online (computer viruses and such). And make no doubt, there's plenty of that out there.

Enter the router, a good companion for your modem, your computer and you. With a few wires and connections and installing some software, you're modem, router and computer get connected.

A router does two special things by leeching on to your modem. (Well, three.)

It can take the digital signal from your modem (which the modem gets from the cable company's cable) and share it with (route it to) other computers in the house. You now have a computer network at home.

In order to do this, the router monkeys with and modifies the IP address on your computer(s). Just by doing that, it automatically makes it hard for hackers to now get at your computer. In fact, it's harder to target any specific computer linked to the router.

A wireless router allows you to connect your Internet connection at home with any wireless device, such as a laptop, Smartphone or iPad. (Make a note: you just need to make sure your wireless network is secure. That information comes with the router.)


To summarize: A modem will only allow 1 computer at a time to go out to the internet.

You need a router installed after the modem and before the switch

 

[doctore]

doctore, he says he has a modem, he does not say he has a router, there in lies the problem.

Still waiting on the make and model of the modem.

I hear you, but most modems come with router functions - he said DHCP was enabled - something must be running the dhcp server, and if by "switch" he really means Level-2 switch, then it's not it.

But I see what you are saying, I should rephrase to "DHCP settings of the modem".

 

[AddRAM]

A modem is a modem and a router is a router.

The switch is not the problem.

The pc is not the problem.

 

[doctore]

A modem is a modem and a router is a router.

Far from it, my modem is also a router, for example. A router doesn't have to necessarily be a separate box, many modems these days come with both integrated routing and switching capabilities. Whether the router will be integrated into the modem box or a separate device - it's irrelevant.

What is also irrelevant is the brand of his modem. Networking devices operate on standards. It's clear that he has a DHCP issue, so a look at the dhcp settings is the best way to determine the problem.



P.S. I just saw that you edited your earlier post...with tons of erroneous information, to boost. You have no idea what a router does, apparently. So I will explain it to you really quick:

routers simply connect networks and they do so based on IP addresses (Layer 3 in the OSI model)

As far as connecting your modem directly to your computer - you can't do this unless:

1. You have entered a proper static IP.
2. Your modem offers DHCP services.

If your modem has DHCP - that means it has a router, as only routers (and layer 3 switches) can switch traffic based on IP addresses. Which also brings us to NAT, another router feature that a modem would not have. What the modem does, let's say a cable modem, is to translate your Ethernet frames to DOCSIS, for instance.

 

[Ztruker]

Here is a nice, simple (sort of) explanation of what a switch is and does.

No, a switch cannot perform NAT and translate public(s) IP addresses into private addresses.
A switch is a network device that filters and forwards packets between LAN segments. Switches operate at the data link layer (layer 2). So, they are not aware of IP addresses which are network layer (layer 3). A switch keeps a record of the MAC addresses of all the devices connected to it. With this information, a switch can identify which system is sitting on which port. So when a frame is received, it knows exactly which port to send it to, without significantly increasing network response times.