Some company preferences can be overridden by subsidiary-level preferences (OneWorld only), role-level preferences, and user preferences set by individual employees. You can disallow individual overrides of company preferences on the Overriding Preferences subtab of Setup > Company > General Preferences.
To prohibit individual overrides of company preferences:
Go to Setup > Company > General Preferences.
On the Overriding Preferences subtab, clear the Allow Override box next to the preferences you do not want to be overridden by individual user preferences.
After you have prohibited an override, individuals cannot set their own preferences. Note that it is not possible to prohibit overrides of company preferences by subsidiary-level or role-level preferences.
A company preference may have been set on one of the preferences pages available from the Setup menu by an administrator or by other users with setup permissions, or may be system-generated.