The OS X El Capitan v10.11.4 Update is recommended for all OS X El Capitan users.

The OS X El Capitan v10.11.4 Update improves the stability, compatibility, and security of your Mac, and is recommended for all users.

This update:

• Adds the ability to passcode-protect notes containing personal data in Notes
• Adds the ability to sort notes alphabetically, by date created, or date modified in Notes
• Adds the ability to import Evernote files into Notes
• Adds support for sharing Live Photos between iOS and OS X via AirDrop and Messages
• Addresses an issue that may cause RAW images to open slowly in Photos
• Adds the ability for iBooks to store PDFs in iCloud, making them available across all your devices
• Fixes an issue that prevented loading Twitter t.co links in Safari
• Prevents JavaScript dialogs from blocking access to other webpages in Safari
• Fixes an issue that prevented the VIPs mailbox from working with Gmail accounts
• Fixes an issue that caused USB audio devices to disconnect
• Improves the compatibility and reliability of Apple USB-C Multiport Adapters

Enterprise content:

• Fixes an issue that could cause a black screen after logging in as the root user
• Fixes an issue that prevents using screen sharing to remotely click the Allow button or Always Allow button in Keychain Access
• Fixes an issue that prevents Migration Assistant from opening when automatic login has been disabled using a configuration profile
• Fixes an issue that prevents Mail from showing the date and time of certain Microsoft Exchange calendar events
• Provides compatibility with the Cisco AnyConnect VPN client
• Improves the reliability of connecting to a Personal Hotspot via Wi-Fi

For detailed information about the security content of this update, see Apple Security Updates.

How to update your Mac

Use the Mac App Store to install the update. It's a good idea to back up up your Mac before updating. Some updates become available only after installing other updates. You should install all available updates, and allow installation to complete without interruption. You can also get this update from the Apple Support Downloads site. You might have unexpected results if third-party OS X modifications have been installed, or you modified OS X in other ways.