Even with Covid, we are doing some “on site” work. Had a call for Wireless Troubleshooting, where the presenting symptoms were an ability to connect to the wireless with some devices but not others, and printing was very slow. The customer said the router had been rebooted several times. This was in an assisted living facility, so first had to establish that the customer had cable through the assisted living facility company, and a firewall/router/wireless to generate a LAN in the apartment.
Eventually, found the primary root cause was the cabling being mixed up on the router with the wrong cables being plugged into the WAN and LAN ports. Generally, regardless of brand, routers (or “all in ones” like comcast devices that also include a modem) have one port which is often a different color for the “WAN”. Think of the WAN port on these devices as where the connection needs to plug in from the street, where there is one and only one unique WAN port for this. Frequently devices also have 4 interchangeable “LAN” ports for devices behind the firewall inside the network (e.g., where computers or printers can be be physically jacked in with an ethernet cable).
So in this story, the wireless was on and could be seen by various devices, which happens when the router is generating a wireless network. But because of the cable snafu, no internet access. Once the right cable was plugged into the WAN port, voila. Worth noting, some of the devices that had connectivity, were actually on other “open” networks in the facility, so that led the users to think in some cases they had internet on their own network, when in fact they were piggybacking on someone else’s network (maybe not a big deal, but a security problem, and generally not “best practice”).
The printing turned about to be something we’d describe as a “not helpful” with HP printers, that they generate their own wireless network which has the word “direct” in it. This means you are printing directly between your computing device and the printer, rather than having the printer on your network connected to the wireless/router/firewall (so printing goes from the compute device, through the router, to the printer instead directly from compute device to the printer). We generally disable this “direct” feature, as it seems to be confusing, get in the way and not work very well (possibly might be used for “public” use, for onsite customers but there are also probably better solutions for that). Once the direct printing was disabled, and the network was functioning correctly (per the cable fix described above), the printing started working as desired given that all devices were on the same LAN.