Hello Pierre B,
Thank you for posting in Q&A forum.
1.Make sure Microsoft Edge is properly installed and up to date.
2.Make sure Microsoft Edge WedView2 is installed. It is required to use Quick Assist.
Here is a troubleshooting guide about Quick Assist for your reference:
Troubleshoot problems installing and running Quick Assist - Microsoft Support
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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