Mac EFI firmware updates enable OS X Lion Internet recovery
A few EFI firmware updates are available for some MacBook and Mac Mini systems that enable Lion Internet recovery on them.
Apple has made a few EFI firmware updates available this week for Mac users who own a MacBook, 13-inch MacBook Pro, or Mac Mini system from mid 2010, which give these computers the capability to start up the Lion recovery routine via the Internet. In addition, the Mac Mini update fixes a problem with the setting for restarting after a power failure not being retained.
The updates are small downloads of about 3MB in size that should be available via Software Update for relevant systems, but can also be downloaded from the following Apple Support Web pages:
- Mac Mini (Mid 2010) EFI Firmware Update 1.5
- MacBook (Mid 2010) EFI Firmware Update 2.1
- MacBook Pro (13-inch, Mid 2010) EFI Firmware Update 2.5
The updates require OS X 10.7.2 to install, and when downloaded and run will provide on-screen instructions for how to apply the updates. Be sure to follow the instructions exactly, and have your system plugged into a reliable power source when updating. It is not uncommon for computer systems to restart multiple times and show temporary black screens when firmware updates are being applied, so allow the system to go through its steps without interruption. An interrupted firmware update can render a system inoperable, requiring replacement of major system components.
When the update completes, the system should reboot to the log-in window or to the desktop, and if you check the boot ROM or SMC version in the system information utility you should see a version string of MB71.0039.B0E for the MacBook Pro, MM41.0042.B03 for the Mac Mini, and MB71.0039.B0E for the MacBook.
To use Lion Internet Recovery, once these updates are installed all you need to do is hold Command-R when starting up and the system will present a request to join a network if you do not have a local partition with the Lion Recovery tools on it. Once a network connection is established, the system will run some diagnostic tests and then download and run the Lion Recovery tools (they are about 200MB in size).
If you own a MacBook Pro or iMac system purchased in 2011, which does not have the capability to use Lion Internet Recovery, then you may need to update its firmware, which can be done by downloading and applying the update for these systems from Apple's Lion Internet Recovery firmware update Web page.
As always, be sure you back up your system with Time Machine, a system cloning tool, or another full-system backup option before applying these or any other updates.