These are instructions on how to disable and re-enable Spotlight indexing on Mac OS X Yosemite, Mavericks, Mountain Lion, and Lion.

Disable Spotlight
Launch Terminal from the Applications:Utilities folder.

Input the following command into the Terminal window and press Return.

sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist

Enter your administrative password when prompted.

Notice Spotlight no longer functions as it did.

Enable Spotlight
To re-enable spotlight simply enter the following command into the Terminal window.

sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist

Spotlight will begin indexing again and the feature will work as it did before.

You can set your computer to log out automatically after a set period of inactivity. This helps ensure that your information is secure when your computer is unattended.

Choose Apple menu > System Preferences, click Security & Privacy, and then click General.
Click the lock icon to unlock it, and then type an administrator name and password.
Click Advanced.
Select “Log out after … minutes of inactivity.”
Set the amount of inactivity time before the system automatically logs out.

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