Steps To Reproduce :
1.Navigate to Control Panel > Configuration > System Settings.
2.Click SSO and find "OpenSSO" configuration in SYSTEM SCOPE.
3. Enable OpenSSO. Save these settings.
4. Navigate to Control Panel > Configuration > Instance Settings.
5.Click SSO and find "OpenSSO" configuration in VIRTUAL INSTANCE SCOPE.
6.Disable OpenSSO. Save these settings.
7.Reopen the "OpenSSO" configuration in system settings, you can find the checkbox enabled is checked. Then update these setting.
The System Setting should override the Instance Settings. (The checkbox should be checked)
The OpenSSO settings in Instance Settings also disabled. Don't override by System Settings.