Netgear c7000v2 cable modem/router no longer working with comcast

[txt9900]

I have had my Netgear wifi cable modem router (c7000v2) for a little over two years on Comcast cable internet service.  It suddenly stopped working, but the lights are all still on indicating it's working.  Worked with Comcast support and they told me to unplug the modem for about 20 seconds and let it re-boot.  But this did not help either and could not get on the internet.

This same thing has happened with my previous Netgear wifi cable modem router (c7000v2) which only lasted two years and the power light I remember turned red.

Do these modems only last about two years?  I am afraid of buying another Netgear modem/router because it's now two modems that I have experienced issues with about every two years.  Any suggestions or solutions?

I remember those old Motorolla Surfboard modems used to last forever.  Netgear needs to improve its quality of modems.

[txt9900 · Accepted solution]

I performed the hard reset.  Re-configured the cable/modem router.  After re-provisioning it with Comcast, it now works fine.  Back up and running.

Thanks.

[plemans]

They do last longer than 2 years. My in-laws are using my old C7000 from almost a decade ago. 

do you have a screensnip of the cable connections page and event logs? That helps to check the connection

[txt9900]

Unfortunately, I don't have screenshots.  I work from home and tried re-booting the cable modem/router but that did not solve the issue.

Then I had to resort to my old Linksys CM-3016 modem and an old Netgear N300 router.  Comcast had no issue provisioning the Linksys cable modem and get me working.  So, it's not my cable connection.

I did some research later and then saw you can do a hard reset of the Netgear AC1900 unit.  Then I did the hard rest with a pin.  

But I have to call comcast and see if they can re-provision the Netgear AC1900 again, to see if the hard reset solves the issue.  

[FURRYe38]

Please post a copy and paste of the C70000 modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

[txt9900 · Accepted solution]

I performed the hard reset.  Re-configured the cable/modem router.  After re-provisioning it with Comcast, it now works fine.  Back up and running.

Thanks.

[FURRYe38]

Glad thats all it took.

Be sure to save off a back up configuration to file for safe keeping. Saves time if a reset is needed.
https://kb.netgear.com/24231/How-do-I-back-up-the-router-configuration-settings-on-my-Nighthawk-rout...
Enjoy. 📡

[txt9900]

I am having issues with my wifi where anytime I type in a URL such as www.att.com , it says the site can't be reached. Get this message on various sites  Just started happening yesterday. I did a factory reset using a pin and holding down for about 20 seconds.  I have xfinity cable and they do not have any sort of outage.

I tried the same with my laptop connected via ethernet and the sites open without any issues.

Now, I try to login to routerlogin.net or 192.168.0.1 via ethernet and I get the following message in the browser.  I cleared the cache of the browser.  Ever re-started my laptop.

Is my cable modem/router gone?

Server Error

404 - file or directory not founds.

The resource you are looking for might have been removed, had its name changed, or is temporarily unavailable.

[txt9900]

Have a backup on my laptop.  Unfortunately the backup doesn't help if I can access 192.168.0.1

Any solutions?

[FURRYe38]

Does 192.168.1.1  not work either? 

When you factory reset, try with the ISP coax cable disconnected from the modem. Seen you can get back in thru the setup wizard. After completing the setup wizard, reconnect the ISP coax cable. 

After you back in, please post the following from the modems web page:

Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

[txt9900]

After I connected the coaxil to the modem/router I was able to get online.  However, noticing that when I try to type out a URL such as www.att.com  etc. get message 'site can't be reached" on multiple browsers.  Also, with multiple laptops.  This is through wifi.  If I try this via ethernet it loads fine.

I know those sites are not down as I tried various such as www.espn.com , etc.  Only happens on wifi.  The only thing I did was a factory reset because I started noticing this issue last night.  Is there some setting in the modem/router that I need to look at?

[FURRYe38]

Would be curious doing a quick test, with WiFi Security set to NONE, no WPA any, Connect laptops to same SSID in the open and see if they connect to those sites. Re-enabled WPA2 and AES after testing. 

Same laptop connect via ethernet to those sites? 

Ya odd that wireless is doing this and not wired. 

[txt9900]

Yeap, the laptops through ethernet connect to any site.  Seems to be something with wifi.  It's not like I am out of range on Wifi.  I am in the same room as the cable modem/router and maybe in the next adjacent room which normally isn't a issue.  Maybe the wifi radios are going bad?

[FURRYe38]

Possibly.

If they cant get thru even with WPA disabled, Might either get you a more up to date wifi router or wireless AP that you can connect via ethernet to this gateway modem and disable the modems wifi radios. 

Or turn the modem in to a modem only and use a newer wifi router with the C7000. 

[txt9900]

I was going though the manual and there is a section that talks about MTU value.  I believe the default is 1500.  But not sure this is it.  

"The maximum transmission unit (MTU) is the largest data packet a network device transmits.
When one network device communicates across the Internet with another, the data packets
travel through many devices along the way. If a device in the data path has a lower MTU
setting than the other devices, the data packets must be split or “fragmented” to
accommodate the device with the smallest MTU.
The best MTU setting for NETGEAR equipment is often the default value. In some situations,
changing the value fixes one problem but causes another. Leave the MTU unchanged unless
one of these situations occurs:
• You experience problems connecting to your ISP or other Internet service, and the
technical support of either the ISP or NETGEAR recommends changing the MTU setting.
These web-based applications might require an MTU change:
- A secure website that does not open, or displays only part of a web page "

[FURRYe38]

Thats the value for most ISP and ethernet connected devices. Yes this is default. Would not effect wireless. 

Most Cable and Fiber ISP services use default 1500. Older DSL ISP services used 1472 or other values less than 1500. 

[txt9900]

ok thanks.  One of these days, when I have some time, I'll try to disable the security on wifi and see if that help connect.  In the meantime I am up and running on my old linksys CM-3016 cable modem with Netgear N300 router,