I continue to come across this issue and it's technical. Many eyes glaze over when you write what it usually is (at least what I run into.) So if it's too technical get help at your location since Canon and others can't know your ISP gear or settings.
Because folk have been clamoring for more security the routers often have the firewalls enabled in the router. I don't want to write at length about how a router already firewalls the internet but the new firewall blocks printers and file sharing on your LAN.
That has to be disabled for printing and file sharing on the LAN to function.
This might be called a firewall or it could be called client isolation.
Another example at https://www.cnet.com/forums/post/186ddf84-c102-49c4-b885-4cce74bfeb92/
Hi,
I am on my 2nd Canon MB5160, first one was replaced due to becoming unable to print wirelessly plus a couple of other issues.
2nd one installed and worked like a breeze for 2 weeks.
Now I have to plug it in to print.
Have tried factory reset, re logging it into my wifi multiple times.
I cannot reinstall the software properly as the printer is not recognised on my network. 2 laptops and 1 phone can't find it.
Canon are offering me my money back as they say it has to be my network.
The printer displays as connected to wifi.
I have tried searching for the printer by IP address, no luck.
I have fibre internet, running Win10 on 2 laptops and Android phone.
Canon say that it is my network and that they have heard of heaps pf problems with people who have fibre.
Does anyone have any ideas please?
Thanks

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