TOTAL DISASTER!!! :-D
OK, so while trying to get the R5 MkII to recognize ANY of my wi-fi SSID's, I tried all the excellent advice you guys have sent my way. I've upgraded the router and repeater to the latest firmware. I've reassigned channels. I tried my iPhone hot-spot (which the MkII DID recognize, which is good to know, but doesn't actually help me practically.)
So while I was working last night, suddenly it seemed like my NAS (big disk array on my LAN) died. All my Word's and Excel's started freaking out. PC's ipconfig reported the usual network was down replaced by... something I didn't recognize. The PC couldn't log into the admin pages of the router, repeater, disk array, or connect with the Linux computer, laptops etc. Tried rebooting the PC. Tried rebooting the router. All dead. All my photos, all my everything... gone.
But the internet still worked at least.
I was thinking about what it could be. One laptop could talk to the disk array fine so nothing lost after all. But how many changes did I make that I'd have to back out?
I opened up my iPhone to check for SMS, and it was still on the Personal Hotspot page. Well, I don't need that I guess, and the split second I turned it off, the PC came back to life.
Basically the main computer had decided to use the iPhone as its internet connection when I plugged in the USB to charge the phone, and dropped its connection to the LAN...
I'm an old guy and this was like a top 5 computer yikes for me in my life.
I have an appointment for the main Canon service center in Ginza (the Fifth Avenue of Tokyo) Friday afternoon, but I can just try a walk-in too, which worked for me last week when I verified the flash shoe connector cover really was supposed to be that hard to get off.