Hi Ian. I'm Greg, 10 years awarded Windows MVP, specializing in Installation, Performance, Troubleshooting and Activation, here to help you.
This is one reason we need the full software package and not an app installed because it will set the scanner utility to start with Windows so it's on standby to scan from the scanner.
The driver for your scanner is here:
https://en.canon-cna.com/support/consumer_produ...(64-bit)
Open the CanoScan software and look for setting to start with Windows. This should be automatically set when the software is installed, however.
You may want to uninstall it in App Settings and reinstall to get it set to start with Windows.
The WIndows 10 driver should work for Windows 11.
Make sure the Scanner is set to start with Windows in Task Manager > Startup Tab, and also in msconfig > Services tab.
Feel free to ask back any questions. Based on the results you post back I may have other suggestions if necessary.
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