OK...glad you made some things clear
first, do not enable proxy server. that is special form of networked "web" server setup that a normal household would NOT have. if you enabled it, that may have been the or part of the problem. it's now looking for something that isn't there. you should also NOT do port forwarding & you should leave the receiver with DHCP turned ON unless you know how to use static IP addresses.
and I would not try to update the FW again before you try a factory reset. if the update you already did went to completion & the receiver worked, then the receiver would not accept the same version again...it would say it was already updated.
my advice, given for the 3rd time, is to try a factory reset using the buttons on the front panel - this is described in the manual on page 76. Resetting the System:
and if this doesn't clear the goofed up network settings, then set it to:
remove any IP address you entered and make sure DHCP is turned ON. the IP addresses should then grey out. reboot the router, let it re-discover the receiver & assign an address. DHCP means the receiver will automatically get its IP address from your router, just like your router uses DHCP to automatically get its IP address from your cable modem - internet provider. Turning DHCP off means you will enter your own static IP address & will also have to configure the router to use that same IP address for your receiver. if the IP addresses are not the same, with the same subnet mask (most typically for home use is 255.0.0.0 or whatever your router says) then absolutely NO connection will occur between the receiver & router - a broken network connection - which may be what happened to you.
Proxy Server - OFF
Parental Lock - OFF
Network Standby - probably OFF but I don't know what the default setting is for sure
remove any Friendly Name you entered if any
the manual DOES explain all this but it assumes the user knows basic networking, the lingo & what these settings do. if you didn't know what they do or understand what they even mean, then you should have left them alone!
it is NOT Pioneer's responsibility to teach people networking, since this is computer/IT/networking realmy & you can either take basic networking classes, buy a Home Networking for Dummies kind of book on basics or get instructions on how to use routers, etc from the company that makes the networking gear.
My advice to you going forward is once you get it straightened out, DON"T CHANGE working network settings! leave them set at factory defaults! the only settings you should touch are those specifically needed for using Pandora...check the manual, I don't use Pandora so don't know off the top of my head what these are but you set them up once to use Pandora.
Your initial problem sounds like a Pandora setup issue, and once again, it is NOT Pioneer's job to tell you how to troubleshoot your Pandora setup & account.. You should contact Pandora, go to their tech support web site for help or call Pioneer.
Plugging in players, cable, etc are pretty straight-forward conventional use of a receiver. But randomly changing network settings, on the computer IT side of things, when you don't even know what they mean isn't a smart thing to do.
Since nobody knows exactly what you changed, no one can say with certainty what will make it connect again to your home network. That's why I tell you to forget turning it off & on, which won't accomplish a dam thing, or trying your FW update again. just do the reset first, get back to ground zero and see if you can get it to connect again.
keep us posted so once you do the reset, someone who knows Pandora might be of help. but you have to restore network connectivity first. after reset you'll need to re-do MCACC, etc, but this can wait until after you make sure you got connectivity again. NOTE: factory reset will probably not automatically make Pandora work again; for that, you'll need to set it up again for Pandora just like you did the 1st time.