A Windows 'troubleshooter' actually shot a trouble!
Been using Win since 1983, and this is the FIRST time that a Win 'troubleshooter' actually did something!
My Comcast connection has been twitchy for the last couple weeks. It's not cable trouble because it often returns to normal after a cold reboot. It has to be software or firmware in the computer or the modem. The systray icon claims "Internet available", which indicates that some level of the system sees the net.
A few minutes ago, just for kicks, I tried Win's Network Troubleshooter. It reported that "some websites are available", which seemed odd because I couldn't access anything. I clicked into the next step, and it came back reporting that the trouble couldn't be found.... BUT normal web service was immediately restored.
Must have been something in the DNS software. I remember reading a hint about cleaning the DNS list.
This:
ipconfig /flushdns
Might try that next time.