Hi Alan Freeman, preventing the Microsoft Edge browser from launching on Windows 10 startup is quite simple, you can do this directly within the Microsoft Edge settings, just follow my instructions below:
1. Open the Edge browser. 2. Click on the three dots in the upper right corner to open a drop-down menu, then click on "Settings" within that menu.
3. In the new tab, click on "System and performance" in the sidebar menu on the left.
4. Under "System" you need to deactivate the option "Startup boost" by pressing the toggle switch on the right side of this option (The Toggl Switch shouldn't be blue afterwards).
After you have made these settings in Microsoft Edge, the browser should no longer start when you launch Windows 10. I hope I could help you with your problem.