Acquire a Secondary Startup Volume

You can’t replace your car’s oil filter while the engine is running; it not only would be messy but could potentially ruin the engine. Similarly, some repairs can’t be done when your Mac is running from a disk that’s experiencing problems. In these cases, you must start your Mac from another volume. You may also need to start from another volume if your internal hard drive or SSD dies completely.

Every version of macOS since 10.7 Lion has included a feature called macOS Recovery (or OS X Recovery)—an extra, hidden Recovery HD startup volume you can use in an emergency to perform repairs or restore a Time Machine backup. Macs introduced in 2011 or later, as well as some 2010 Macs, also support Internet Recovery (see Start in Recovery), which does basically the same thing but works even if your startup drive is missing or damaged. In addition, starting with the 10.11 El Capitan version, Disk Utility can repair most disk errors even when you run it on the volume you booted from—a neat trick! With those three options, the majority of Mac users already have a suitable secondary startup volume, perhaps without realizing it.

Despite these alternatives for starting your Mac, however, I suggest having another startup volume available. I say this for several reasons:

• Although the in-place Disk Repair feature in El Capitan and later is handy, it can’t fix every type of disk error—and, of course, it won’t help you at all if you’re running 10.10 Yosemite or 10.9 Mavericks.

• Some Macs that can run recent versions of macOS don’t support macOS (or OS X) Recovery, and even on a supported Mac these features might not always be available (for example, if the part of your startup volume that contains the hidden Recovery HD volume is damaged, or if you’re without internet access).

• If you manually changed your Mac’s partition structure or restored the entire startup volume from a backup, Recovery might not work.

• Even in the best cases, the solutions built into macOS don’t let you run third-party disk repair or backup software (which is sometimes essential to solving problems)—and in the case of Internet Recovery, booting can be extremely slow.

A secondary startup volume can take numerous forms. I prefer an external hard drive with a Thunderbolt or USB 3 interface, because it’s fast and flexible and can be used for things other than starting up in an emergency (backups, for example). But that’s just one of several options. Be sure you have at least one of these handy:

• The USB Software Reinstall Drive included with certain Macs.

• A USB flash drive, or even an SD card (for Macs with built-in SD card readers), on which you’ve installed a bootable copy of macOS

• A bootable flash drive supplied with third-party disk repair software, such as DiskWarrior.

• An external Thunderbolt, USB, or FireWire hard drive or flash drive on which you’ve installed a bootable copy of macOS.

• Another Mac that can boot into USB, Thunderbolt, or FireWire target disk mode—assuming both Macs have matching USB-C, Thunderbolt, or FireWire ports, and the second Mac is running a version of macOS that’s compatible with the first Mac. (To make this work, first shut down the Mac whose disk you want to boot from. Then connect the Macs with a USB-C, Thunderbolt, or FireWire cable, start the Mac whose disk you want to boot from, and hold down the T key on that Mac’s keyboard until you see the USB, Thunderbolt, or FireWire icon.)

• A second internal drive or a second partition of your main startup disk with a bootable copy of macOS.

If your secondary startup volume already contains a bootable copy of macOS, you’re all set. But if you’re using another disk or partition, you must first install macOS on it. You can do this in any of the following ways:

• Clone your internal drive. Using backup software designed for this task, make an exact copy of your main startup disk on the secondary disk. Tools that work well for this purpose include Carbon Copy Cloner and SuperDuper!.

• Install macOS directly. In many cases you can run the macOS installer, selecting your secondary disk as the destination.

After setting up your secondary startup volume, be sure to test it to verify that it is bootable; you don’t want to find out that it’s not working after your main drive dies. Read Start Up from Another Volume for more details.

Get a Disk Repair Utility

Over time, disks (including SSDs) frequently develop minor errors that can cause your Mac to behave badly. The specific causes and symptoms are numerous, but when disk errors occur, your only option is to use a utility that’s specially designed to examine the disk at a low level and repair the problem. (In some cases, you must run the disk utility from your secondary startup volume. See Run Disk Repair Utilities for further instructions.)

Apple includes a basic disk utility called (you guessed it) Disk Utility with macOS. It’s found in /Applications/Utilities as well as on the hidden Recovery HD volume. If you’ve cloned your startup volume or installed macOS directly onto another disk, you already have one disk repair utility ready to go.

I use Disk Utility frequently, because it’s a quick and easy way to solve a number of problems and is considered to be extremely safe. But some disk errors are too complex for Disk Utility to repair and, unfortunately, such errors are not uncommon. So I’ve long recommended, if at all possible, having a second disk repair utility available—one that can pick up where Disk Utility leaves off.

However, this story has changed somewhat since the release of High Sierra. For unknown reasons, Apple waited a long time before releasing proper developer documentation on the APFS file system (used for all boot volumes under Mojave and for SSD boot volumes under High Sierra). Thus, most third-party disk utilities still—even in early 2019, under Mojave—have limited support for APFS. On the other hand, I’ve noticed a sharp decline in disk errors since switching to APFS, so the unavailability of disk utilities that support it has been mostly moot, in my experience.

If you are running Mojave—or if you’re running High Sierra on a Mac with an SSD—you should probably postpone decisions about third-party disk utilities until all the major players have updated their offerings. However, if you have an older version of macOS, or if you’re reading this book well after its publication in early 2019, it’s a good idea to pick a third-party disk repair app.

In my opinion, only three are worth any serious consideration:

• DiskWarrior from Alsoft is my favorite because it can solve some problems that no other utility can. It’s been around for over 20 years and has only gotten better over time. DiskWarrior ships on a flash drive that you can use to boot your Mac (although you may need to run an included app to update it, or use an adapter to connect it to your Mac, depending on your Mac model).

  The latest version of DiskWarrior available at publication time, 5.2, is not yet capable of rebuilding APFS volumes, but the developer is working on adding full APFS support.

• TechTool Pro, Micromat’s flagship repair utility, not only repairs disks but also checks your RAM, video card, and other hardware components. TechTool Pro includes a feature called eDrive that’s somewhat like Recovery, in that it lets you boot your Mac from a hidden volume to repair it.

  Although TechTool Pro 10.1.2 (the current version at publication time) runs on Mojave and can repair APFS volumes, the eDrive tool and the Protogo tool (which makes bootable repair volumes) don’t work in Mojave, the Volume Cloning tool doesn’t make bootable clones, and the Volume Structures test can’t unmount Time Machine volumes to test them. Updates to address these shortcomings are in the works.

• Drive Genius from Prosoft Engineering doesn’t have the same long history as the other two candidates, but it has a solid feature set and can repartition disks without erasing their data (although that feature does not, as of publication time, work with APFS-formatted volumes). Drive Genius’s BootWell feature enables you to create a startup volume to be used for repairs.

  Drive Genius runs under High Sierra and Mojave, but its Defragment, Repartition, and Rebuild utilities don’t yet work on APFS volumes as of publication time (when the current version is 5.3.0).

Any of these apps can also be installed on most types of secondary startup volume, such as a bootable duplicate or a flash drive on which you’ve installed macOS.

Set Up Another User Account

Your home folder (/Users/your username) contains all the files that are specific to your account, including not only your documents, pictures, and music but also preference files, caches, and certain kinds of application support files and system add-ons. If you’re the only person who uses your Mac, you may have only one login account and therefore just one home folder.

Regardless of how many users your Mac has, I suggest setting up an account to use solely for troubleshooting. That way, when a problem arises, you can easily switch to the other account—which will have default settings for everything—and see whether the problem still occurs. If it doesn’t, you know the cause is to be found somewhere in your home folder, and you can begin narrowing it down from there.

To set up a troubleshooting account, follow these steps:

1. Go to System Preferences > Users & Groups.

2. Click the lock icon, and enter your username and password.

3. Click the plus button just below the list of accounts.

4. Enter the requested information: Full Name, Account Name (a short version of your name, such as your initials or first name only), and Password, and optionally enter a password hint.

1. Choose Administrator from the New Account pop-up menu.

2. Click Create User.

Consider Purchasing AppleCare+

AppleCare+ (formerly known as AppleCare Protection Plan) is essentially an extended warranty you can buy for a new Mac. Normally, Apple offers a one-year limited warranty on its computers, including 90 days of telephone support. AppleCare+ extends the warranty (and the telephone support) to a full three years.

Depending on which equipment you purchase, AppleCare+ can cover certain Apple-supplied accessories, and for desktop Macs it even includes onsite service in most areas. The cost for AppleCare+ depends on your hardware; it ranges from $99 (for a Mac mini) to $379 (for a 15-inch MacBook Pro).

I can’t emphasize strongly enough what a great idea AppleCare+ is. In the course of one year, my mother, my wife, and I all had faulty iMac logic boards replaced—at no additional cost—thanks to AppleCare+; without it, the machines would have been out of warranty and we each would have spent many hundreds of dollars for the repairs. If you don’t live close to an Apple Store or an authorized repair center, Apple will send you a prepaid shipping container in which to return your laptop for repair.

You can purchase AppleCare+ when you buy your Mac, or any time before your initial one-year warranty expires. You don’t have to buy it from Apple; some resellers, such as Amazon and Expercom, often sell it for less. Because it provides not only hardware repairs but also (usually) competent telephone tech support, I heartily recommend AppleCare+ to everyone buying a new Mac.

Think About an Insurance Policy

There are some serious computer problems—such as theft or accidental breakage—that no amount of troubleshooting can fix. To protect your investment in cases like these, consider buying a special insurance policy just for your computers.

You may already have homeowner’s or renter’s insurance that covers your Mac in the event of fire, flood, or burglary. But read your policy carefully, since you may be surprised to learn that many common types of loss are usually not covered—things like accidental damage or theft from a car. (And, in cases like these, your Apple warranty or AppleCare+ plan is of no use either.) Policies geared specifically for computers can fill that gap.

True story: A number of years ago, I was carrying a Mac laptop in a padded laptop bag. The bag slipped off my shoulder and hit a rock, and the Mac’s display cracked. Because I had a computer insurance policy, though, I saved hundreds of dollars on the costly repair—even after factoring in the deductible and the cost of the policy itself.

For many years, Safeware was the best-known source for computer insurance in the United States, but now the company focuses entirely on business and education customers, and it appears that individual consumers can no longer apply for coverage. However, a quick web search will turn up other insurers with computer-specific policies, such as Worth Ave. Group. Another option is SquareTrade, which covers hardware failures, drops, and spills (for newly purchased equipment only)—but it does not cover theft, fires, or other types of damage. In the UK, computer insurance policies are available from companies such as CompuCover.

Find Extra Help

Last but not least, figure out who you can call or email for advice when you can’t solve a problem on your own (even with this book).

Have an Accessible Copy of This Book

One last little detail: When it comes time to solve problems, you may not be able to use your Mac at all, so if you’re reading this ebook on your Mac, you won’t be able to refer to it. For this reason, if you have a second Mac, an iOS device, a Kindle, or some other gadget that can display ebooks, be sure to keep a copy of this book there. If not, consider printing the remainder of this book.