This message appeared after I logged on yesterday. The server is 127.0.0.1 port 8800
I'm running Windows 7, connected to Comcast. The other computers on this connection have no problem.
I have never requested a proxy server -- had to do some review to understand its function. I don't know how this connection was established. Comcast says it isn't theirs. This address gets a 502 Bad Gateway.
I went to Network Settings > Internet Properties, and unchecked "Use a proxy server ... , OK
back to Internet Properties, the Apply control is dimmed. OK, back to Network Seetings, and
"Use a proxy server" is checked again. I clicked Advanced, cleared the proxy address, got a "Do you want to turn off the proxy connection?" clicked Yes. The "Use a proxy server" box is now unchecked.
Exit, Return, the box is checked again.
I set up a new Administrator account, got same results.