To eliminate this annoying pop-up you have to eliminate all files an references. The article above doesn’t eliminate them ALL. So this is how you properly eliminate all files and references, since some of them are not visible. You should have done this in the first place.

- Applications> Utilities> Keychain Access
- File> Delete Keychain “system”

The following message will give you 3 options;

- Select “Delete references & files”

Quit Safari> Go on Safari

The message; “A Keychain cannot be found to store “safari”‘ will pop-up.

-Select “Reset to defaults”

Then you will need your admin password
and done

*If you have don’t have the admin password (make a new admin to delete or reset the other admin’s password);

– Reboot
– Hold apple command + s down after you hear the chime.
– When you get text prompt enter in these terminal commands to create a brand new admin account (hitting return/enter after each line);
◦ mount -uw /
◦ rm /var/db/.AppleSetupDone
◦ shutdown -h now
– After rebooting you’ll have a brand new admin account.

When you login as the new admin you can simply delete the old admin password or simply reset the password.

You don’t need administrative account access to do this.