Geez, this is a pain. I already wrote up my message in preparation to submit here, but this web forum has pasting disabled. Well, I'll input it all manually again, but not wasting time to proof before submit, so please excuse any typos.
Printer: Canon PIXMA TS6420a inkjet
OS: Windows 10 Home x64 21H2
I followed the instructions at:
on getting the printer connected to my wi-fi router/modem. It then says "Click <icon> in the taskbar, follow the on-screen instructions to proceed with setup." The icon looks like a blue downward arrow through the hole in a CD. There is no such icon in the taskbar (or in the systray). Apparently Canon omitted what software to run to present that icon when describing how to manually setup wi-fi config using the printer's LCD display.
The printer was previously connected via USB to my printer in the initial setup (using their online guide which eventually has me download their software to follow its instructions). After that initial setup via USB, the printer appears in the "Printers & scanners" wizard as "Canon TS6400 series". After doing the above wi-fi setup (but getting halted at the "Click <icon> in taskbar" setp), another instance of the printer shows up as "Canon TS6400 series (Copy 1)".
When I look at the properties of those printers, the USB printer shows up as "USB001, CanonTS6400series, Canon TS6400 series" (port, description, printer name). The 2nd instance shows up as "WSD-e3960d7-d27c-4cc5-8c76-8761c70bedbd, IPP Port, Canon TS6420 series (Copy 1)". IPP means Internet Printing Port, so I'm guessing the 2nd instance of the printer is accessed via wi-fi ... maybe. I'm trying to setup the printer for both USB access (from my computer) and also for wi-fi access (from wi-fi devices), but I've yet to try finding the wi-fi printer from, say, my Android smartphone or iPad tablet to allow print jobs from them to this printer. That's another hurdle to endure.
Although the printer purports to support both USB and wi-fi connections, does it support both access methods at the same time? That is, can the printer be connected to both a USB port on my computer, and also concurrently connected to my wi-fi router/modem?
Alas, when I log into my cable modem's internal web server to review its settings, connected devices are listed as either "Ethernet" (wired LAN) or as "Wi-Fi (2.4G|5G)". They are identified by their MAC addresses, not by device names. I cannot tell which MAC address(es) belongs to the wi-fi printer.
Also, during the manual wi-fi setup using the printer's LCD screen, it scanned for wi-fi devices to which it could connect. My wi-fi modem supports both 2.4 GHz and 5 GHz bands. The printer only found the 2.4 GHz band of the cable modem. Does this printer's wi-fi radio only support the 2.4 GHz band? I would prefer the 5 GHz band which has shorter range (but the printer is only 10 feet through open air to the modem), but also has faster bandwidth along with less interference from other 2.4GHz devices (e.g., cordless phones, microwave ovens, etc).
"(Copy 1)" is non-descript, so I renamed the USB-attached printer from "Canon TS6400 series" to "Canon TS6420a (USB)", and the IPP-port-attached printer from "Canon TS6400 series (Copy 1)" to "Canon TS6420a (IPP)". However, just because my computer has a device on IPP port doesn't mean the printer is really accessible by other wi-fi devices. I can't be sure the IPP port on my computer means other wi-fi devices can access the printer via wi-fi. My cable modem just shows MAC addresses for the wi-fi connected devices, so I can't tell if the printer is actually connected via wi-fi to my wi-fi cable modem.