Two ideas:
- try your local Canon support, for example https://www.canon.com.au/ is their Australian support
- ask the companies IT-support to solve it (it's their job, not yours)
What happens if you connect a brand new third PC to the network, install the drivers on it and try scanning from it. Or connect it to the second PC and try to scan from the first.
That kind of experiments might show where the issue is located.
We have an ethernet network with two desktop computers and a number of mobile devices. So we bought a network printer, which is connected to one of the two desktops via usb. Until last week, I was always able to use the scanning function from the other desktop computer, but somehow that's no longer possible. I've tried removing and reinstalling the device, to no avail. Either the scanner is not even seen, or when the computer does see the scanner, selecting the Scan function does nothing.
I've posted a question on the Canon forum but got no response. Canon won't allow me to post a question to their support section via email because I'm not in the US. Lastly, the retailer where I bought the printer is out of ideas to try.
Can anyone here help me?
Thanks in advance!

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