System preference greyed out how to fix ?

You''ve got the system in a strange condition - you have one attribute grayed out (the first checkbox about setting the time for a required password) and another attribute able to be checked/unchecked (disable automatic login). Normally they are both greyed out if the padlock is locked or both able to be set or unset.

These attributes are saved in your screen saver preferences and system preferences plist file located in ~/Library/Preferences/com.apple.screensaver.plist (the "Requires password" and time settings) and ~/Library/Preferences/com.apple.systempreferences.plist (the disable automatic login setting).

Since the first is all you want to change, quit System Preferences for a bit, then in a Terminal window, try looking at what they are:

defaults read com.apple.screensaver

There are only three parameters here, namely askForPassword, askForPasswordDelay and tokenRemovalAction. The first is either 0 or 1, the second is the time in seconds to wait before requiring password after sleep or screen saver begins (only 0, 5, 60, 300, 900, 3600, 14400 and 28800 are possible choices) and not sure what the last one is. What values do you have for your account for the first two? Try setting them to this:

defaults write com.apple.screensaver askForPassword 1

defaults write com.apple.screensaver askForPasswordDelay 300

Then start up System Preferences again - does that help or make a difference when you look at what the Security & Privacy settings are now? If not, try quitting System Preferences again, then moving the com.apple.screensaver.plist file to your Desktop and then starting up System Preferences and forcing it to create a new one. Can you change them now after unlocking the padlock?

If you move the com.apple.systempreferences.plist file, you might want to make some screen captures of the different System Preferences that you've changed or are important to you before moving the file, so you can easily get the system back to the state that you like. You can also save these preferences first to a text file before moving the plist file with the Terminal.app command:

defaults read com.apple.systempreferences > systempreferences.defaults

Ask questions if you're not sure of something.

Good luck...

Read the article : How to display a screen saver on your Mac - Apple Support

Click on drop down arrows in require password to change the timings .

I unchecked the box require password after .. an pop up appeared .Did you clicked turn off screen lock .

Click the lock on the bottom left where is says "Click the lock to make changes".

May I suggest something simple that works for me? Check the box next to Show a message when the screensaver is locked. For me, that activates the choice on the right.

If the lock is open when you made the screenshot, lock it; then open it again with your password and try again as per Dialabrain. If that does not work, try the Eric Root trick.