In order to enable screen lock on MacOS, you must follow these steps on all user accounts on your workstation:

• Click the Apple icon on the top left of the screen
• Select "System Preferences"

• Select "Security and Privacy"

• Enable "Require password after sleep or screen saver begins".

• Ensure the time value is less than or equal to 15 minutes

Then, you either:

1. Configure display sleep time for your workstation for both battery power (if you have a laptop) and AC power:

• Go back to "System Preferences"
• Select "Battery"

• In the left-hand column, select "Battery"
• Modify "Turn display off after" such that this value is no more than 45 minutes

• Next, select "Power Adapter"
• Modify "Turn display off after" such that this value is no more than 45 minutes

2. Alternatively, enable screensaver:

• Go back to “System Preferences”
• Select "Desktop & Screen Saver"

• Modify "Start after" such that this value is no more than 45 minutes