This site is saying "invalid HTML removed from your post" which sounds like paranoia/incompetence/ passive-aggressive / Bad forum design.

History/background/context:

Windows 10 PC

Absolutely no access to another computer

Absolutely no access to any functioning cell phone.

Amazon page where I bought computer says:

CyberpowerPC Gamer Xtreme VR Gaming PC, Intel Core i5-9400F 2.9GHz, NVIDIA GeForce GTX 1660 6GB, 8GB DDR4, 240GB SSD, 1TB HDD, WiFi Ready & Win 10 Home (GXiVR8060A8, Black)

Amazon page where I bought the modem says:

ARRIS SURFboard SBG10 DOCSIS 3.0 Cable Modem & AC1600 Dual Band Wi-Fi Router, Approved for Cox, Spectrum, Xfinity & others (black)

Wireless router is Netgear model R6400v2, no memory of where or when purchased.

when originally purchased, I believed the computer had a wifi router built in.

It certainly has antennas sticking out of the back of it.

However, even after literally days of struggling with tech support, I never got that to work.

It is very important for you to understand that this aspect has NOTHING to do with the current external router, which has worked in the past.

Getting Errors "Wifi does not have vailid IP configuration" and "Ethernet does not have valid configuration"

The official Windows forum showed a "solution" that called for many steps, one of which led to having to go into Windows Settings and click the Network Reset Button......that button does not exist on my computer, as screen shot number 13 shows.

Conditions that led to this situation:

1. I have never wanted or needed wireless internet, just used a coax cable connected to a modem;

2. A pro-wireless friend gave me a gift of an Echo Dot, which wouldn't work unless I had a wireless router. At great expense and reluctance, got a Netgear model R6400v2.

3. Alexa did work, but not reliably or in ways I wanted it to. Alexa pretty much reluctant to obey, and very eager to sell me things. Not what I want in my home.

Adittionally, internet speed of the Netgear was disgusting, something like 13MBPS, when the modem was 115MBPS. . Deep anger at lost time and money. Disconnected the Echo and the Netgear.

4. Many weeks later, cell phone stopped working, could not make outgoing calls, and tech support insisted to get it functioning again, I had to have a wireless connection.
Reinstalled Netgear, but cannot get phone to connect to it. Tried using hotspots in four areas outside my home, can't launch phone. Gave up.

5. Came home, have installed Netgear exactly as before, installed Echo device exactly as before. I was surprised to discover that I could make outgoing calls using only the Echo, without the phone, no idea at all how that works.

6. Unwilling to live with the sickening slow Netgear internet speed, took it off, took Echo off.

7. weeks later, needing very badly to make an outgoing call, connected echo and netgear again, exactly as before.....and suddenly the Netgear won't connect me to the internet. Cables, connections are all identical to as before. Router is less than two feet from the computer.

8. This launched the process you see shown in the screen shots, trying to solve this, steps I have already taken. As of this posting I have rebooted computer, modem, echo and router at least 25 times. The shots are numbered as best I could in the order I took the steps. The screen shots can be seen on the site Bleeping Computer under the title "Cannot Put Up My Topic"

Update:

Hooked up to the internet exclusively with modem only, no router:

Went back to the Netgear manual, shown here:

https://www.downloads.netgear.com/files/GDC/R6400v2/R6400v2_UM_EN.pdf

Note on page 13 it shows a very specific illustration showing correct cable hookup. That configuration has worked fine in the past, no longer working.

Next, I go to the Troubleshooting section of the manual, which leads to the Netgear website.

On this page, I click on Guided Assistance: https://kb.netgear.com/27199/I-can-t-access-my-router-what-do-I-do

This is a series of yes/no questions. The first question is "Are you able to access the internet or other websites?"

Now, maybe it will be helpful to explain my way of thinking. To me, this question only confuses and enrages me. First of all, how could I be reading a web page if I did NOT have access to the internet, since that is where this question appears, on the internet. Next, did the question REALLY mean, will the ROUTER access the internet, and if so, why didn't they phrase it that way.

So right there, with question number one, I am stuck. Is there something inherently wrong with me, or is this "help" thing totally broken?

I choose "no".

This produces:

"Ensure that you have internet access. Try visiting other websites to see if they are accessible.

If you do not have internet access, you will need to set up your router.

Refer to the link:

How to install a NETGEAR router

Are you able to access other websites? "

Well, I've hooked up, rebooted and tried dozens of "fixes" for the router and each time I tried more than one website, so the answer to this would be "no". My concern is with this troubleshooter. It's confusing. Which do I choose? I don't have internet access WITH THE ROUTER, but I do have internet WITH THE MODEM. So, do I follow the link "how to install router" or do I click "no" in answer to "are you able to access other websites?"

I suppose I have to try both, and if one fails, I will have to restart this entire process. Below you will read me referring to this point as "the branch".

To be clear: a coax cable runs to my modem, then an ethernet cable is connected to the modem, then to the computer, and everything works fine.

If I follow the cable setup shown in the netgear manual, run ethernet from modem to router, then connect router to computer with another cable, that does not work, I cant' get online. That setup used to work and I have no clue what has gone wrong.

So, first, following link "how to install router":

This begins with an illustration of cable hookups that does NOT match the illustration in the manual, using nighthawk. The cable to computer hookup is missing from this illustration. The page then goes on to tell you to install the Nighthawk app. Since I have no access to a working cell phone, I go here:

Note: If your product is not supported or if you prefer to install your router using a computer, see the following knowledge base topic: How do I set up my NETGEAR router using the router web interface?.

This leads here:

https://kb.netgear.com/22697/How-do-I-install-my-NETGEAR-router-using-the-router-web-interface

To install your NETGEAR router using the router web interface:

Using an Ethernet cable, connect your modem to the yellow Internet port on the back of your NETGEAR router.
Connect your computer to one of the Ethernet ports on your router.
Press the Power button on the router.
The LEDs on the router light.
Open a web browser and enter routerlogin.net.
You are prompted to log in.
Note: If you experience any Internet connection issues, try power-cycling your network. For more information, see How do I power cycle my home network?.
Log in to the router.
The default user name is admin. The default password is password.
The user name and password are case-sensitive.
Click ADVANCED > Setup Wizard.
Select the Yes radio button and click Next.
The router detects your Internet connection.
You are prompted to log in.
Enter and confirm a new admin password.
Select and answer two security questions.
Click Next.
The Congratulations! page displays.
(Optional) Click Print this to print your network settings.
Click Next.
The Firmware Update Assistant page displays.
If a firmware update is not available, click OK.
Your router is set up.
If a firmware update is available, click Yes to update your firmware.
The firmware updates.
The router reboots.
You are prompted to log in.
Enter admin and the new password you created earlier.
The BASIC page displays.
Your router is set up.

Gonna have to pause and resume this later, as following these steps is going to disconnect me from the net.

Resuming now: At step 4, it isn't possible to connect Chrome or Firefox. I've followed the Power Cycle instructions to the letter, at least two dozen times, and nothing will get the router to regain access.

so, reopening the troubleshooter, at the branch I mentioned above, I now choose "no", and this leads to "you will need to contact Netgear support" , leading me Here: https://www.netgear.com/support/contact.aspx

This asks me to enter my serial number, which I do, very accurately. The "Next" button remains disabled even though I enter the serial accurately. I even tried changing the two Zeros with the letter "O", did nothing.

So, now I am dead in the water.....about three full days of work, just to get Alexa to function, because I desperately need to make an outgoing phone call, and my cell phone isn't working.

If you want to look at what is wrong with the cell phone, I can post chat transcripts of the "tech support" fails.

Forum Discussion

model R6400V2 wireless router cannot connect