ann_neesa239 Said:
"I tried to login on apple website, it was successful but I'm still unable to open the system setting. any other way I can go about it?"
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If System Settings Won't Open:
A. Boot in Safe Mode:
In Safe Mode, Login Items do not run at login, certain preferences are set aside, and damaged system files are then reset. So, once booted in to Safe Mode, wait 30 seconds, and then boot up normally, attempting another update install. For instructions, go here: How to Use Safe Mode on your Mac - Apple Support
B. Single-Out this User:
Try an Admin new user, see if you do not get this occur while in it. If so, then it is an issue with the configuration of the current user. If not, then it is an issue with the entire Mac.
No success?...
C. Reinstall the macOS:
Nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to reinstall macOS from macOS Recovery - Apple Support.Important: Be certain to create a backup of your Mac prior to performing the reinstall. That way, you can have something to restore from the Mac from, should anything go wrong with the reinstall. Once reinstalled, try this once more, seeing if you still get this error.