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PC and Mac backup: How to protect your data from disaster

First, choose your preferred backup strategy from our three options, based on your own personal preference and practicality. Then follow our step-by-step guide to achieving peace of mind. What do you have to lose?
Written by Ed Bott, Senior Contributing Editor

Most people who've developed a sensible backup strategy did it the hard way, after losing precious data to a disk crash or a power surge, or losing an entire data-filled PC to a thief or in a natural disaster like a fire or flood. That sinking feeling as you realize you'll never see those files again is painful and unforgettable.

The natural response to that sort of loss is to resolve to never let it happen again. But devising an effective backup strategy, one that works without requiring a lot of extra effort, takes organization, planning, and forethought.

Where do you start? It's a four-step process.  

Step 1: Choose your backup approach

In my experience, you have three backup strategies to choose from. Which one you choose involves equal parts personal preference and practicality. The biggest factor to consider is whether the data you need to back up is work-related or strictly personal.

Just keep the important stuff

This approach is for people whose PC is primarily for casual personal use. If your IT department takes care of managing your work laptop and backing up work-related files to your company's network, you only need to worry about personal files: photos, home movies, and important documents. Backing up those crucial files to your preferred cloud service is the most logical solution.

If your system drive has a catastrophic failure, you'll have to reinstall your operating system and apps, but you don't have to worry about losing those important files, which are safely tucked away in the cloud.

Back up all your data files

On a PC that you (and possibly other family members) use for work, school, and personal tasks, you might want to ensure that every data file for every user account is backed up for quick recovery in the event of a problem. You can back up everything (except the operating system, apps, and saved settings) to the cloud, a local drive, or both.

This option lets you recover older versions of a file or folder after accidentally deleting it. It also allows you to retrieve an older version of a document that's been overwritten by more recent work. And it gives you the option to recover all data for all users if you migrate to a new PC, replace your primary storage, or reinstall your operating system from scratch.

Create a system image that you can restore to a new PC or Mac in case of disaster

This option is the one to choose if business continuity matters more than anything else. It's labor-intensive initially, and it can require intermediate-to-advanced technical skills, but it will save you a tremendous amount of time if you need to recover quickly from a crash or upgrade to a new PC or Mac with the absolute minimum of downtime.

A system image includes everything on the target drive: Hidden configuration files, installed programs, settings, and data files. Typically, the image file is saved on an external drive, connected via USB; with the right software, you can save an image file to another PC or server on a local network or in the cloud.

Done right, a backup image is a perfect clone of the system configuration at the time it was taken. That means, of course, that you have to find a way to back up data files and other system changes you make after that image is created.

Both Macs and Windows 10 PCs include built-in software that can help with this task. MacOS has Time Machine, which can be used to do a full system restore. Windows 10 has a pair of utilities: the legacy Windows Backup client, which does image backups, and File History, which handles backups for data files in common locations.

If you choose third-party software, you can choose fairly sophisticated routines that capture occasional full images along with differential or incremental backups to keep you covered.

Step 2: Organize your data files

What do you have to lose?

Everyone has a collection of personal files they would absolutely hate to lose. That video of your firstborn taking his first steps? The PDF copies of your tax returns for the last five years that the bank wants before they can process your mortgage application? The CV or résumé you need to send to the recruiter offering you the job of your dreams?

That's not to mention all your other personal photos and videos, plus digital music and media files that you bought or downloaded long ago that aren't available on streaming services, as well as folders full of work, school, and personal documents that aren't on anyone else's server.

Oh, and don't forget program installers, product keys, license info, and other digital details you'll need when you're restoring apps after a crash.

Many of these files can be re-created from online sources, although that can be an extremely tedious process. But some of the items on that list are absolutely irreplaceable, and keeping your only copy on a hard disk that is one cosmic ray (or spilled cup of coffee) away from an unrecoverable crash is foolhardy, to say the least.

So, what do you have to lose? Answering this question means identifying the files and folders that mean the most to you and then organizing them into a handful of known locations that you can target for backup. That last step is key: The more your important files are scattered across multiple locations, the more likely you are to end up with an incomplete backup.

And even though you might prefer an idiosyncratic organizational structure, I recommend that you keep everything in well-known folders managed by the operating system: Documents, Downloads, Photos, Videos, and so on. For Windows 10 PCs, that's your user profile folder. On a Mac, it's the Home folder for your user account.

Step 3: Choose where to store your backup copies

Which backup destination is right for you? This one's a multiple-choice question, with the available answers being:

  • Cloud
  • Local
  • Both

As far as I'm concerned, copying your most important files to the cloud and then syncing them to multiple local devices is the core of an effective backup strategy.

Putting those files in the cloud means you're not at the mercy of hardware failures. And a catastrophic failure of the cloud provider is a low risk, especially if you store with a provider that has engineered redundancy and fault tolerance into its system and has the financial wherewithal to survive an economic downturn. Microsoft, Google, Amazon, and Dropbox are unlikely to go out of business anytime soon, so having a Plan B is prudent but not quite as urgent as preparing for a local disk crash.

Privacy and security are not trivial concerns here, but depending on your preferences (and your budget) those concerns can be dealt with by choosing your cloud provider wisely.

The bigger problems with the cloud are, of course, the cost of storage and the limitations of bandwidth. Those problems intensify as your cache of data grows larger. Consumer plans like Microsoft 365 give you access to as much as a terabyte of storage for a few dollars per month. But your Internet service provider might have a thing or two to say about that, as upload/download caps can turn the process of backing up and restoring from the cloud into a multi-day activity. And you can be hit with unexpected charges or slowdowns if the total goes over your data cap.

So, a local drive is better than the cloud? Well, yes, at least sometimes, for some tasks.

Storing your backups on a local drive means you have ready access to them and can restore your files as fast as your external hard drive and your storage bus can deliver them, unencumbered by any limitations of your cloud provider or your broadband connection. But those local copies are vulnerable to some of the same risks as the PC containing the original data. If your home or office is destroyed by fire or flood, your local backups are likely to disappear along with the PC they're backing up.

Clearly, the most complete strategy involves a hybrid approach, with important files safely stored in the cloud and copies of that big cloud store synced locally. And maybe another copy in a safe deposit box or other offsite location. Just in case.

Step 4: Make sure your data is being backed up properly

A backup you can't restore is worse than no backup at all.

Checking the status of synced cloud data files is fairly simple: Just compare the contents of the remote folder with your synced local copy. Local backup images need more attention.

Good backup software allows you to schedule regular backups and notifies you after each operation runs, giving you a heads-up if it encounters any errors. But that's only half the job. If business continuity is the goal, you need to test your backup image to confirm that it can easily and quickly be restored. You definitely don't want to discover that your image file is damaged or corrupted when you're under the gun to restore it right away.

If you have a spare PC or Mac handy, you can use it as a testbed. Some third-party software allows you to mount a backup image as a virtual drive or restore it to a virtual machine, which greatly simplifies the burden of testing. But whatever you do, don't skip that step.

So, what's in your backup plan? Share your experience and advice with other readers in the comments below.

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