CAX80 won't work at all on WOW Internet; firmware update ruined it

What FW version is currently loaded? What FW was loaded for the router side of the modem? 

Was the FW updated on the modem side from the ISP? Modem FW can ONLY be updated by the ISP. 

Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

Received the second replacement today. Did absolutely nothing with it until I called WOW. This is the extremely detailed process I went through in calling WOW, so be prepared for a long read.

TL;DR VERSION: It's definitely WOW, and not a darn thing got resolved on the 2h15m call.

The WOW tech rep had me connect the coax cable for the first time, and then plug in the power supply to turn it on for the first time. All lights came on and cycled on like you'd normally expect -- including the 2.4 and 5G symbols, and the push-button symbols at the bottom.

During this time, I gave the WOW tech rep my MAC address so he could activate it on the ISP's end. (I had no Internet connection up to this point, but I wasn't saying anything as I was unsure what he had to do on his end.) He then confirmed my MAC address, and asked me to unplug it for 30 seconds, and then plug it back in. He then allowed 2-3 minutes for a reboot to happen.

During this reboot, the 2.4/5G symbols and the push-button symbols did not light up at all. It was just the top four lights, as well as the 1 flashing for activity for the ethernet connection of my laptop in the first port.

Once the 2-3 minutes passed, I still had no Internet connection, and suddenly it went into a reboot. This was a repeat of everything I had been experiencing in mid-November, and the two prior units, and the repeated calls with WOW tech support.

The tech rep took longer than that 2-3 minutes to speak again, and he asked me to connect to the Internet. I told him I had no Internet connection. He asked to confirm my MAC address again. He then went silent for a few and then said he did something on his end and to allow 2-3 more minutes. My unit rebooted during this. The rep confirmed that I was using a modem/router combo from Netgear.

Mid-reboot, he asked me to power cycle the unit by unplugging it. I waited a couple of minutes, then he asked me to plug it in, and allow it to reboot. Once again, everything lit up except for the 2.4/5G and the push-button lights. No Internet, either. There was no change in status. I told him as much. And it rebooted yet again. And once that finished, still no change in status.

Clearly, everything is being caused by WOW. At this time, I took over the call and just flat out told the rep that whatever WOW did in mid-November, it has "bricked" my unit from working. I could safely hypothesize it was a WOW issue from mid-November, because if the modem/router was incompatible with WOW, it would not have worked when I got it in mid-September, and not worked for approximately two months without a flaw.

He sent another signal and it rebooted. During this, he tried to say that a tech needed to come to my house. I said no, because in October, we hooked up all brand new wiring from the outside hub for the neighborhood to support the speeds I upgraded to. Everything was working perfect. There was no need for that because that wasn't the issue.

He took my info to escalate this, but I said maybe let's try to speak to someone in escalated tech. (When he said we needed a tech sent to my house, that was about the point I realized the tech rep had served his purpose and could not provide any more help.) He transferred me to the escalation team.

I explained everything to the new rep. She agreed that perhaps it was the signal from WOW being sent out that was causing the issue. She said maybe it was too strong of a signal. She sent me to an escalated troubleshooting team that can do more looking into things. I confirmed with her this wasn't the basic troubleshooting team I just got done talking to.

I was put on hold for 40 minutes, then spoke to an agent. She claimed that there is an Internet issue which is preventing modems from being activated. I said that was an Amazon Web Services outage, but this issue has gone on for closing in on a month, so it's not related to AWS. She wasn't able to help much because of the AWS issue, so she said to call back tomorrow. She gave me a direct phone number and a PIN for my case, and I call that tomorrow to repeat this entire process all over again. In the meantime, I swapped back to my old setup, confirmed I had Internet, and the call ended.

So, what the heck, I'll do this tomorrow I guess and see what happens. I have no faith at this point. I will update on this tomorrow. But I really need something to happen tomorrow one way or another. I've spent too much time messing with this.

I'm experiencing the same issue with my CAX80 and WOW isp in Chicago area. Stopped working about 2 weeks ago (worked fine for approximately 1 year) and recently had a WOW technician out to my house. Switched me to my old Motorola modem/router which works but is a temporary solution because it doesn't support full speed I'm getting from WOW. Switched back to my CAX80 to troubleshoot and had a ticket setup with Netgear. Waited 1.5 hours on hold to speak to someone. Had an appointment I had to be at and never anticipated being on hold that long so was only was able to speak to the first Netgear rep for a few minutes. Called back and they had me do troubleshooting to connect to router. Practically begged both Netgear reps I spoke with to look at these forum posts because I feel they accurately describe what is going on and might point toward a larger issue outside of individual hardware. They weren't interested. First rep laughed then told me it wasn't possible that WOW internet wouldn't work on their modems because of all modems being built to ISO standards. Second rep told me to buy a new modem/router and there was nothing they could do. I was told I might possibly hear back from someone via email if they discover a work around but I'm not holding my breath. Feel like I was just told that to get me off the line at that point.

Incredibly frustrating - I think Netgear could learn a lot from what has been posted here by others but it appears to me that the reps have their standard check the box troubleshooting steps they have to follow and won't deviate from that. I'm convinced based off the posts of others, buying a new one would accomplish nothing other than wasting my money. Netgear comes off with being far more concerned about getting you to sign up for their tech support plans than actually listening to a customer.

I’m confused on how it’s an ISP issue. I get the modem could work on a different ISP right now but it was working on WOW up until very recently. If Netgear put out a firmware update that caused it to no longer work with WOW, isn’t that a Netgear issue? WOW didn’t change anything on their end that I’m aware of. I’m not very tech savvy, is there something I’m missing?

The WOW rep I talked to a few days ago said they were aware of issues with Netgear modems and it didn’t sound like they had any plans to do anything about it.

My final update:

I re-reviewed ISP prices in my area. WOW is by far and away the best I can get for the monthly price. Nothing else compares at all. Staying with WOW is the intelligent decision.

I then bought a CAX30 at Best Buy (which, for all intents and purposes, is the model that is just a step down from the CAX80, and you'll see that if you do a side-by-side specs comparison.) The CAX30 supports 1GB speed, which is the plan I have, and it has all the functionality that I will need for a proper modem/router combo unit in my household.

I activated it with WOW a couple of hours ago, and I haven't had any issues to speak of in this very small sample time. I am getting the speeds that I should. I am surfing websites and streaming videos like normal. I guess the fact that it booted right up and worked right away was amazing to me in itself, after all the issues I was having with the CAX80. I will need more of a sample size to confidently say this, but the CAX30 is likely my final solution.

As I previously said, based on everything I have experienced, and based on others' experiences, I am convinced that WOW has done some sort of update to its system in the second half of November 2021 that somehow suddenly "bricked" the CAX80. But my patience in continuing to push the issue with WOW had worn very thin, because multi-hour calls were just draining, and you never could seem to talk to someone physically in the United States. There is definitely a disconnect between what WOW has done and what info the overseas call center has.

As for my CAX80 unit, and another CAX80 unit that Netgear sent me under warranty for free with nothing expected in return (don't ask me how that happened; it just did), in the next couple of days, I will be putting them up for sale on eBay. In doing so, I'll explain nothing is wrong with the units, but it was this ordeal with WOW, and that prospective buyers that have WOW should probably avoid this unit as it's confirmed not compatible right now, and may never be compatible ever again for all we know.

I am also operating under the idea that I will be losing money on this entire situation due to having to buy a different model unit, even with the fact I have two CAX80s to sell. I will try to speak to WOW customer service on the billing side to try and get an account credit for my troubles, given the amount of times I have called them.

I hope my thread has helped some of you find comfort and realize other people are going through the same thing. Whether some of you follow my lead in buying a different model unit, or decide to switch ISPs, or decide to continue the campaign to get WOW to understand, I wish you the best of luck. And I may keep up on this thread for a while until the activity simply dies down and it isn't posted in for weeks. Maybe I'll add a supportive comment or two, who knows? Otherwise, consider this the end of my active involvement in the issue, as hopefully, the CAX30 does not repeat history and I don't ever encounter my CAX80 issues ever again.

My sons CA80 stopped working. I reset it back to factory and was unable to reinstall it. I went to best buy and bought another one and spent the day making numerous calls to wow trying to install the new one. Wow sent a technician that changed some splitters outside and came inside and showed me on his meter that we had a good signal. He attempted to install both the old CAX80 and the new one to no avail. We installed an older modem router temporarily. 
There is definitely something going on that this router is having a problem with WOW or the routers have turned into expensive boat anchors.

I continue having issues with CAX80.  Went through soft and hard resets multiple times, worked with support team to determine what's wrong with it, got an OK to replace under warranty .... AND to add insult to injury the support team didn't work with me on the return / exchange for new gear, just because I had Covid and sent in my paperwork late by a day.  All my emails got completely ignored.  It's a shame how I got treated, especially considering the top of the line equipment that we are talking about.