Usually means there's a version mismatch between opera.exe and files in the version folder in the install folder.
If you renamed opera.exe to something else to work around the Microsoft family issue and Opera updated, you'll need to delete your renamed opera.exe and rename the new opera.exe.
Another way to do things is to uninstall Opera (don't choose to delete your data when uninstalling unless you want to) and delete its install folder afterwards. Then, reinstall Opera.
If Opera won't uninstall, you can delete its install folder manually. Then, delete all Opera shortcuts. Then, in the Windows Task Scheduler, select "Task Scheduler Library" and delete all the autoupdate tasks for regular Opera and its assistant (leave the Opera GX ones there). Then reinstall Opera.