You should back up your Mac before installation.Fixes an issue that could allow a user to install pre-release software even when the setting is disabledįor detailed information about the security content of this update, see Apple security updates.Adds the ability to create mobile accounts with the createmobileaccount tool.Addresses an issue where OS X systems bound to directory services could stop responding under certain conditions.Fixes an issue where a website could prevent the user from navigating away by presenting repeated JavaScript alerts in Safariįor enterprise customers, this update includes the following:.Resolves an issue that could delay outgoing email messages in Mail.Addresses an issue that could cause Photos to unexpectedly quit after importing some Leica DNG files.Improves reliability when syncing photos and videos to iCloud Photo Library.Improves the reliability of upgrading iPhoto and Aperture libraries to Photos.Addresses an issue that prevented some external displays from functioning properly.Improves Migration Assistant reliability.The OS X Yosemite v10.10.4 update improves the stability, compatibility, and security of your Mac. The OS X Yosemite v10.10.4 Update is recommended for all OS X Yosemite users.

Upgrade to mac os 10.10 yosemite