Hi @Barry Sayer
Double-check if the normal user's account has been granted access permissions to the shared printer. You can verify by going to the shared printer object and clicking on the "Access control" menu on the left.
Here is a thread as well that discusses the same issue and you can try out some troubleshooting steps from this and see if that helps you to sort the Issue.
Universal Print - Error Sent to Printer
https://techcommunity.microsoft.com/t5/universal-print-discussions/universal-print-error-sent-to-printer/m-p/1886550
Below is the link for common troubleshoots that can be helpful for you.
Universal Print troubleshooting guide
https://learn.microsoft.com/en-us/universal-print/fundamentals/universal-print-troubleshooting-support-howto
Hope this resolves your Query!!
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