I'm putting this out here as a last-ditch effort before canceling my service. Verizon has tried really hard to solve my problem, but my last hour+ support call ended with them telling me they had exhausted all options and there was nothing further they could do for me.
Last Thursday, four devices in my house stopped being able to connect to our network, which they had all been connecting to since last August without issue. Another half dozen devices have continued working flawlessly.
Symptoms:
* Affected devices see network at half or very weak strength even when standing right next to router and right next to unaffected devices that show full strength signal. Sometimes network signal disappears entirely.
* Affected devices that try to connect get error messages like "Authentication error," "Disabled," or in the case of an Android phone networks just show "Saved" and will attempt "Connecting..." but never connect and just revert back to "Saved."
* Affected devices: Google Pixel, iPad, Chromecast, laptop (unknown make, belongs to my basement tenant). Unaffected devices: iPhone (5 Ghz), Chromebook (5 Ghz), Dell laptop (5 Ghz), Roku TV (5 Ghz), Roku stick (2.4 Ghz), Chromecast (5 Ghz). (Yes, there is one Chromecast that connects and one that won't.)
Solutions we attempted:
* Connecting to 5, 2.4, and guest networks.
* Verified that MAC address filtering is disabled.
* Tried different broadcast channels.
* Disabled all security and tried to connect to unsecured network.
* Factor reset gateway.
* Replaced gateway with new equipment.
* Changed SSIDs.
* Unplugged network extender.
* Power cycled network extender.
* Moved gateway router to other side of house and trying to connect from there.
* Looked for firmware updates (none available).
* Rolled back firmware to previous version.
None of the above worked. Everything about the symptoms suggests that this is a signal interference issue, except we can't locate the source of the interference that suddenly appeared last week.
* Two my neighbors have FIOS and I can see their network names, but on unaffected devices they show with just a bar or two while my own network shows full strength. The houses are a good distance apart and since channel switching didn't help I don't think they are interfering.
* Used WiFi analyzer app on my phone (which is one of the affected devices) and didn't see any sources of interference.
* There are no other routers in the house.
Mystery:
* When I log in to router settings and view my network, there is a device named "Chromecast" which shows its connection type as Coax. This device connected itself automatically when a brand new router was set up, as you would expect a coax connection to do. I'm not sure if this device has always been there - I never looked at the list in a huge amount of detail until there was a problem, and I have rental tenants who connect a lot of devices so I am used to not knowing all the device names. However I do think it's weird that a Chromecast would show up as a coax connection given they don't use coax. The Verizon techs all had no idea what it could be either, but part of me wonders if this device has somehow intruded on my network and caused a problem. I actually went outside the house and disconnected the coax line that carries signal to my tenants' set top box so that I could verify the device was not located in their apartment - when I disconnected the coax line their set top box disappeared from my network but the mystery Chromecast did not. I blocked the device using the router management interface, but that did not resolve my problem. This may not even be related but it seemed worth mentioning.
Any brilliant ideas we haven't tried?