My elderly father in law has an iMac that I have to “fix” every time we visit. I would like to manage his account with lite parental controls, but I cannot seem to remove his administrator rights in the Users & Groups page of the System Preferences.
Log into your own separate administrator account and go to his account page in the 'Users and Groups' pane. Then click on the checkbox marked 'Allow user to administrate this computer.' You must be logged in on a separate administrator account (which you will want anyway with your setup).
It should look something like this under his name in the Users and Groups pane:
The 'Allow user to administrate this computer' option you mentioned is not available to me.
How do I downgrade an administrator to standard user?
