Hello, PeterRM. Thank you for posting to the Apple Support Communities. We know that being able to scan images with your Mac is important, and we can certainly help you in this situation.
From what we gather, you are seeing a connection error when you attempt to scan a document to your Mac at this time. It sounds like you have started with some great troubleshooting steps already, and we’re happy to help you continue from here.
There are several reasons why a connection error may appear when you attempt to print or scan using your Mac. To start, we’d like to help by making sure that your scanner is set up using the suggested steps. The following Apple Support articles will help you ensure that your printer is enabled correctly:
Set up a scanner to use with Mac - Apple Support
Scan images or documents using your Mac - Apple Support
If you are seeing that your printer has been enabled correctly already, there are more steps to try if you are noticing problems when scanning. Please review the following article for help:
Solve scanning problems on Mac - Apple Support
If you continue to notice an issue after using these steps, we can help you more. To continue, can you tell us if this printer is connected with a wire, or wirelessly?
Have you been able to scan images successfully in the past using your Mac?
If you have any other computers to test with, can you tell us if you’re able to scan images there instead?
We hope that this information helps you and we look forward to your reply.
Cheers!