7 Mac Startup Options Every OS X User Should Know Recovery Mode Starting with the release of OS X Lion in 2011, Macs have offered a Recovery Modethat users can access to diagnose hardware issues, restore Time Machine backups, manage hard drives, and even reinstall OS X itself. To use Recovery Mode, reboot or start your Mac and hold the Command and Rkeys simultaneously on your keyboard as soon as you hear the familiar startup chime. Keep holding as your Mac boots, which may take a few moments depending on its specific configuration. You can let go of the keys when you see a screen similar to the screenshot below. Recovery Mode is possible thanks to the installation of a hidden recovery partition on your Macâs hard drive, and allows the user to perform the aforementioned tasks without needing an OS X DVD or USB installer. To perform recovery tasks on older versions of OS X, such as OS X 10.6 Snow Leopard, users needed to boot from the install DVD. A recovery partition will be created by default on new OS X installations and upgrades, but not every Mac configuration is supported, including RAID system drives. Further, if your Macâs drive lacks a recovery partition for any reason, you may still be able to access OS X recovery tools via OS X Internet Recovery, which loads the recovery information directly from Appleâs servers. To use this feature, youâll need an active Internet connection and a Mac introduced after the public availability of OS X Lion, which includes the Mid-2011 MacBook Airand up. Startup Manager Most Mac users will probably only ever use the single drive that came with their system. But for those who want to use multiple internal drives or partitions, Windows via Boot Camp, or boot to external drives, youâll need to use the Macâs built-in Startup Manager. Simply reboot your Mac and hold the Alt/Option key on your keyboard as soon as you hear the Macâs startup chime. After a few moments, youâll see all of the bootable devices appear on your screen accompanied by their corresponding icons and volume names. Apple KB HT1310 The Mac Startup Manager will update as needed, so if you add or remove bootable drives or devices on your Mac, the list will automatically display the current options. You can use your mouse, trackpad, or keyboard to select the desired drive, and either click on its upward arrow button or press Return once youâve made your selection. As long as the Mac is compatible with operating system contained on the selected drive, your Mac will continue booting the designated operating system. Examples of when you may need to use the Mac Startup Manager include booting to your Windows Boot Camp partition, booting to a complete cloned backup of your system drive, or reinstalling OS X from a DVD or USB drive. The Mac Startup Manager works great if you have a number of boot options from which to choose, but your Mac also recognizes a few additional startup keys that direct it to boot immediately from a specific source. These keys include holding the C key during boot to boot directly from an inserted CD, DVD, or bootable USB drive, and holding the N key to perform a NetBoot to a compatible network server. Safe Boot If youâve ever worked in the Windows world, you may be familiar with Windows Safe Mode, which starts the operating system with the bare minimum level of drivers and software to help you isolate the cause of a software issue or conflict. OS X offers a similar mode called Safe Boot. Just as with its Windows counterpart, OS X Safe Boot should be used to help troubleshoot issues that may be caused by corrupt or incompatible software, or to help isolate software issues from hardware failures. To use it, press and hold the Shift key on your keyboard as soon as you hear your Macâs startup chime. Keep holding Shift until you see a gray progress bar appear beneath the Apple boot logo. When triggered, Safe Boot will force a check of your startup volumeâs integrity, load only the minimum required OS X kernel extensions, disable all user fonts, clear font caches, and disable all startup and login items. All of these tasks equate to a significantly longer boot time compared to the default ânormalâ OS X boot process, so donât panic if your Mac takes longer than usual to boot.Once you reach the usual OS X login screen or desktop, youâll notice the words âSafe Bootâ in red letters in the menu bar. Youâll also likely notice slower overall system and graphics performance, as OS X is using default drivers to help you track down your software or driver issue. You wonât want to use Safe Boot day-to-day, of course, as many common and useful functions are not available in this mode, but it is an essential step in troubleshooting your Mac. When youâre ready to return to ânormalâ mode, just reboot your Mac without holding down the Shift key. Reset PRAM Your Macâs parameter random-access memory (PRAM) stores important information such as the type and identity of your OS X system drive, the presence of any other internal drives, the number and type of connected devices, screen resolution, and speaker volume. If your Mac isnât acting as expected, a PRAM reset is usually the first and easiest troubleshooting step to try. Youâll also want to make sure you preform a PRAM reset after you replace your Macâs hard drive, unless you like waiting five minutes for the system to boot while it searches in vain for the old missing disk. To reset PRAM, shut down your Mac and find the Command, Option, P, and R keys on your keyboard. Youâre going to need to power your Mac up, and then press and hold all four keys simultaneously as soon as you hear the startup chime. Itâs a little tricky at first, and you may miss it on the first attempt, but just keep rebooting your Mac until youâre comfortable contorting your fingers to reach all four keys at the same time. Keep holding the keys until your Mac reboots itself and you hear the startup chime a second time. At this point you can release the keys and your Mac should boot as normal. Note that settings such as resolution and system speaker volume will be set to defaults, so donât be startled if your Macâs startup chime is a bit louder on the second boot. Verbose Mode Thereâs a whole lot going on when your Mac boots, but Apple, always concerned about design and user experience, hides the details behind the familiar light gray boot screen. This makes booting your Mac a simple and pleasant experience, but can also hamper troubleshooting efforts. whatâs really happening during your Macâs boot process, youâll want to enable Verbose Mode, which lets you see the messy details during boot in order to identify any drivers, kernel extensions, or other issues that are causing your Mac grief. To use Verbose Mode, reboot your Mac and press and hold the Command and V keys simultaneously as soon as you hear the Mac startup chime. Youâll soon see quickly moving rows of text instead of the gray boot screen, and you or a tech support rep will be able to see exactly what is causing the issue youâre attempting to troubleshoot. Single User Mode Related to Verbose Mode, Single User Modealso shows you the full details of your Macâs boot process. But instead of finishing the boot and bringing you to the default OS X login GUI, it gives you a text terminal which can be used for everything from advanced troubleshooting to hard drive repair. To boot into Single User Mode, reboot your Mac and hold down the Command and Skeys simultaneously until you see white text appear on the screen. You can begin using the terminal once the boot process finishes and you see root# on the screen. Your Macâs Single User Mode is similar to that found in Linux, and many of the commands are the same between the platforms. Once youâre ready to exit Single User Mode, just use the command âexitâ to restart the system and boot normally. Enable Target Disk Mode Target Disk Mode is a very useful feature exclusive to Macs that, in effect, lets you turn your Mac into an unnecessarily complex external drive. While in Target Disk Mode, you can connect your Mac to another Mac via FireWire or Thunderbolt and see the contents of the Macâs drive mounted on the second Mac as if the drive were an external FireWire or Thunderbolt device. This not only lets you easily access data on a Macâs hard drive, it also lets you use one Macâs hardware to boot another Macâs operating system and data. To use Target Disk Mode, reboot your Mac and hold down the T key as soon as you hear the startup chime. Keep holding until you see a white FireWire or Thunderbolt logo appear on the screen (depending on your Macâs hardware capabilities). You can now directly connect your Mac to another Mac with a FireWire or Thunderbolt cable and access the first Macâs drive. When youâre done, unmount the first Macâs drive from the second Mac in OS X and press and hold the first Macâs power button until the system powers off. Summary Itâs important to read over the description of each Mac startup option to ensure that you understand its use and purpose. Once youâre familiar with these options, however, just use the table below as a handy guide in case you forget the specific keys necessary for each option. STARTUP KEYS DESCRIPTION --------------------------------------------- Command-R / Boot to OS X Recovery Mode ---------------------------------------------- Alt/Option / Access Mac Startup Manager ---------------------------------------------- C / Boot to CD, DVD, or USB ---------------------------------------------- N / NetBoot ---------------------------------------------- Shift / Safe Boot ---------------------------------------------- Command-V / Verbose Mode ---------------------------------------------- Command-S / Single User Mode ---------------------------------------------- Command-Option-P-R / Reset PRAM ---------------------------------------------- T / Enable Target Disk Mode ---------------------------------------------- Want news and tips from TekRevue delivered directly to your inbox? Sign up for the TekRevue Weekly Digest using the box below. Get tips, reviews, news, and giveaways reserved exclusively for subscribers.