Linksys router frustration

[Rustward]

One of the things to keep in mind in this case is this was a working LAN before the switch from DSL to cable. This should have required absolutely no changes on the LAN. Just unplug the router from the DSL modem, plug into the cable modem, then either ipconfig release/renew or just power cycle all devices on the LAN to update the Domain Name Server addresses to those from the new ISP. That's it.
Can't seem to get the OP to say what, if anything was changed on the LAN.

Modhatter, if you reach the point where you are ready to go buy a new router, try a hardware reset on your existing router. There is usually a little recessed button in back that you have to press with a bent paperclip or equivalent. Check the manual for this procedure because sometimes you have to do simultaneous or sequential [-]things[/-] human tricks to get this to happen, like with the power on, press the button and hold for ten seconds while standing on your ear whistling Dixie and patting your head and rubbing your stomach all at the same time. Then you will have to configure the router all over again, but you'll have to do that with a new one anyway.

From what you have posted it sounds like your hardware is functioning properly, but I guess it's possible that it is broken.

 

[modhatter]

Thank you all for your recommendations. I continue to fiddle with it. Meanwhile I am still trying to decide on a new router.
I don't want to be without Internet again. I survived about five days last month, and it was like being taken off drugs (not that I can actually relate)

 

[target2019]

Fiddling sounds like fun! Shut it all down. Do a hard reset on the router. This may mean more than just pushing in a reset button.
Windows can be so helpful at a time like this...