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Best Windows backup software for PCs and laptops

29 September 2026 at 12:00

By now, the importance of backing up your Windows PC or laptop goes without saying. It only takes a moment to consider how much of your data is at potential risk of a drive failure, natural disaster, or a bad actor, if you don’t have a solid backup plan in place. The best Windows backup software includes file backup, sure, but also disk imaging and full image restore, as well as disaster recovery.

Our picks for best Windows backup software are selected with all the must-haves of data backup and recovery in mind, so in the tragic event that your primary local data repository is compromised, you’re fully covered.

What backup utilities come with Windows?

Sadly, while other operating systems make backup easy, Microsoft saddles users with a patchwork system of utilities and holdover imaging tools from Windows 7.

Some of these work well (Restore Points, File History), others don’t (System Repair Disc, Recovery Drive). None are suitable for quick and easy disaster recovery — even the online backup that is available when you use Windows with a Microsoft cloud account.

Thankfully, there are a number of highly capable and far more reliable third-party backup options for Windows that cover the panoply of backup, restore, migration, and disaster recovery.

Why you should trust PCWorld for backup software reviews and buying advice: It’s in our name — PCWorld. Our reviewers have been testing PC hardware, software, and services for decades. Our backup evaluations are thorough and rigorous, testing the promises and limitations of every product — from performance to the practicalities of regular use.

PROMOTION

Backup software powered by AI – EaseUS Todo Backup

EaseUS Todo Backup covers everything you need for backups. With AI smart backup, automate your backup tasks on schedule, run to make copies, do realtime protections, and restore everything instantly. No extra effort is required. Also, get 250GB cloud storage for free.

Now 25% OFF Exclusive Code: PCWORLD25

Free Download

EaseUS Todo Backup 2026 (Home) – Best overall Windows backup for most PC users

EaseUS Todo Backup 2026 (Home) - Best overall Windows backup for most PC users

Pros

  • Imaging, backup, sync, and disaster recovery
  • Comprehensive and option rich
  • Great interface

Cons

  • Occasional non-fatal oddities during file backup and sync
  • No third-party online storage support
Price When Reviewed: Yearly: $39.95 I Perpetual: $59.99 I Lifetime Upgrades: $79.99
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$39.95
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Who should buy EaseUS Todo Backup 2026?

EaseUS Todo Backup 2026 (home) has matured into an outstandingly versatile and comprehensive backup solution. With a still-affordable perpetual license, it also costs less than some of the now subscription-only competition such as Acronis True Image and Macrium Reflect X.

The paid tier of EaseUS is the best all-round home-PC choice for anyone who wants comprehensive backup and recovery with a straightforward “buy once, use forever” license

EaseUS Todo Backup 2026: Further considerations

Imaging, disaster recovery, plain or compressed file/folder backup, sync, real-time (actually continuous) backup, and nearly every bell and whistle in the backup space are accounted for by Todo Backup.

In addition to its comprehensive and reliable set of features, Todo Backup greets you with a pleasingly-rendered, animated interface and a supremely logical layout.

The fact that it doesn’t force you into a subscription model is also a big plus in its favor. That said, if you want to use EaseUS’s cloud storage (third-party isn’t supported directly), you do need to opt for a yearly plan. Fortunately, it’s decently affordable: software plus 1TB of cloud storage for $60/yr.

Read our full Easeus ToDo Backup 2026 review

Acronis True Image – Best comprehensive backup and malware protection

Acronis True Image - Best comprehensive backup and malware protection

Pros

  • Imaging, backup, and disaster recovery
  • Actively protects against viruses and ransomware
  • Integrated cloud storage available

Cons

  • Heavy installation footprint
  • Subscription only
  • Lots of telemetry
Price When Reviewed: $49.99 to $124.99 per year
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50% off original price$24.99
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$34.99
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Who should buy Acronis True Image?

True Image is a great option for anyone who wants seasoned and reliable file and image backup as well as full-fledged protection from malware (including ransomware).

True Image is for users who are amenable to a subscription-only plan, the benefits of which are the iterative and ongoing update potential as well as the inclusion of cloud storage.

Acronis True Image: Further considerations

Acronis established itself as a trustworthy stalwart in backup software years ago. In meantime the program’s moniker morphed for a while to Cyber Protect Home Office (which is actually more descriptive), but is now back again to the more recognizable True Image.

Throughout the changes, the program remained super-reliable, and gradually evolved into a versatile, flexible, backup and malware protection solution. While True Image doesn’t offer support for third-party cloud storage, only its own, the program does allow you to back up to and from network locations.

As I noted in my review, “If you’re looking for a comprehensive, set-it-and-forget-it data-safety solution, I know of nothing better — or comparable for that matter.” This does however, result in a rather heavy system footprint with multiple background processes running.

Alas, for better (the comany’s) or worse (yours), True Image is now subscription-only. I recommend bumping up from the Essentials plan to the Advanced plan, which includes 250GB of storage (with the purchase link in this article, it’s only $24.99 per year, down from $72.99).

Read our full Acronis True Image review

Easeus Todo Backup Free – Best free backup and disaster recovery for Windows

Easeus Todo Backup Free - Best free backup and disaster recovery for Windows

Pros

  • Imaging, file backup, and sync
  • Super-friendly, attractive interface
  • Disaster recovery with boot media

Cons

  • No cloud storage support (a trial is offered)
  • A couple of minor non-fatal file function errors
Price When Reviewed: Free
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Who should use Easeus Todo Backup Free?

Anyone who wants friendly, easy to use backup and reliable disaster recovery in one package should take a look at Easeus Todo Backup Free. The only cost to a startlingly capable suite is a couple of ads and nags.

To clarify the distinction between our paid and free picks, the free version of Easeus Todo Backup includes imaging, file/folder backup, scheduling, and boot media. Cloud storage and deeper advanced features require you to step up to the paid tier.

Easeus Todo Backup 2025: Further considerations

Easeus Todo Backup Free covers all the backup basics: File/folder backup (compressed and plain), one-way sync, system/drive/partition imaging, and all with scheduling. But there are extras you might not expect from a freebie such as backup from network locations, and what EaseUS calls real-time backup (it’s actually continuous — close enough). That’s unique for a freebie.

Todo Backup 2025 also sports the easiest, most attractive (in our estimation) interface on the market. That alone should recommend it to most users. But the fact that it just works (there are a couple of odd, non-fatal peccadilloes in the file sync), and comes with reliable disaster recovery and boot media seals the deal.

There’s a professional version that adds numerous advanced features, as well as EaseUS’s own cloud storage. See the entry above.

Arcserve ShadowProtect SPX – Best Windows backup for SMBs

Arcserve ShadowProtect SPX - Best Windows backup for SMBs

Pros

  • Fast and reliable continuous data protection
  • Super easy restores to real or virtual hard drives
  • Handy timeline overview
  • Excellent disaster recovery

Cons

  • Somewhat daunting login dialog
  • Image-based backup only
  • Pricey for end users
Price When Reviewed: $99.95
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$99.95
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Who should buy Arcserve ShadowProtect SPX?

Home, small, and other businesses who are looking for backup software more powerful than the norm, that also scales nicely in networked ecosystems will do well with this solid, feature-laden, and very fast backup program.

Besides Arcserve’s support for SMB / mixed Windows-Linux environment, it’s heavy on features that are overkill for most home users, but great for the more robust needs of business users.

Arcserve ShadowProtect SPX: Further considerations

Arcserve ShadowProtect SPX is loaded with pro- and enterprise-level features including support for third-party virtual hard drives (VHDs, etc.). It is also an excellent choice for Linux users or those in mixed Windows/Linux environments as it’s available for both operating systems.

ShadowProtect SPX is a bit pricey, but it’s extremely reliable backup software with foolproof continuous data protection. Note that the company no longer targets the average user, but I found that it works exceptionally well even on a single computer.

Read our full Arcserve ShadowProtect SPX Desktop review

Other notable Windows backup software

  • Paragon Backup & Recovery Community Edition: A free program that offers robust file backup that should meet the needs of most users.
  • Perfect Backup:  Fast and competent, this free backup program is more versatile than Windows File History.
  • Aomei Backupper Pro: A complete backup solution capable of preserving your important data both locally and remotely.
  • Aomei Backupper Standard: A respectable free backup program if you can tolerate the occasional ad.
  • Retrospect 19 Solo: Includes support for both proprietary and third-party cloud storage, but sadly it lacks disaster recovery.
  • Retrospect 19 Desktop: The pro version of the above covers all the bases, but has a steep learning curve and high price.
  • Backup and Restore (Windows 7): Conveniently installed with Windows, and good for imaging but bad for disaster recover.
  • MSP360 Managed Backup: Uses a handy web-based console to provide imaging and file backup services for multiple devices at a reasonable price.
  • MSP360 Backup: The free incarnation is a worthwhile upgrade to Windows File History.
  • Iperius Backup: Has power aplenty, but the learning curve and interface might occasionally flummox less-experienced users.
  • Handy Backup 8.5 Professional: Top-notch features that might’ve garnered an Editors’ Choice award had it been entirely glitch-free and a bit easier to learn.
  • MiniTool ShadowMaker Pro 4.6: There’s a lot to like, particularly its unique ability to interface with all computers on a network.
  • Macrium Reflect Home: Would likely qualify as our favorite backup software if it wasn’t relatively pricey. It’s an exceptional program that offers everything we want from backup software — full drive/folder backup, ease of use, reliability, etc.
  • DriveImage XML: A viable free backup solution, albeit only for MBR disks.
  • Ashampoo Backup Pro 26: Overarching support for myriad backup chores with easy-to-understand wizards, but no backup from the recovery disc or option for “differential” backups.

Note that in this article we focus on local-software based solutions, although many also include a cloud component. For cloud-first backup, see our roundup of the best online backup services. Admittedly, the distinction between the two categories is blurring as they each expand their feature sets.

How we test

Our reviewers run each program through the various types of backups and restores it’s capable of — including those requiring boot media. This is largely to gauge reliability and hardware compatibility. We check speed, but such is highly reliant upon the connections and media involved.

If we notice anything is particularly fast or slow, we’ll tell you about it, but creating a functional backup is paramount.

To learn more details, see our article on how PCWorld tests backup software.

Who curated this article

Having started computing by flipping switches, Jon Jacobi has witnessed storage morph from punch cards and tape to solid state. He’s been using and testing HDDs, SATA SSDs, and NVMe SSDs for PCWorld for well over two decades. To paraphrase a well-known commercial, you might say he’s seen a thing or two.

How to choose backup software

If you recently purchased an external HDD or SSD from a major vendor such as Seagate or WD, check to see if there are backup utilities or a backup software license included. Whatever backup software you use, keep in mind the following key aspects of the best solutions: file backup for documents/photos, image backup for whole-PC rollback, boot media for dead-drive recovery, versioning for accidental overwrite protection, and know which are critical to your backup plan.

File backup

If you want to back up your essential data (operating systems and programs can be reinstalled, though it’s mildly time- and effort-consuming), a program that backs up only your important files is essential. Some programs even automatically select the appropriate files or folders. File backup can include operating system files if you wish but is still not suitable for disaster recovery.

Image backup/imaging

Images are byte-for-byte snapshots of your entire hard drive (normally not including empty sectors) or partitions, and can be used to restore the operating system, drivers, programs in one swift, fell swoop. Imaging also ensures that you don’t omit anything important as can happen with file backup.

Recovery boot media 

Should your system crash completely, you need alternate means to boot your system and restore data using your backup software. Any backup program worth its salt should be able to create a bootable optical disc or USB thumb drive. Some will also create a restore partition on your hard drive, which can be used if the issue isn’t a failed drive.

Note that we’ve run into multiple issues with Microsoft’s own Recovery Drive and System repair disc — don’t rely on those.

Scheduling

If you’re going to back up effectively, you need to do so on a regular basis. Any backup program you purchase should let you schedule backups and run them in the background. Some even will backup files as they change (real time) or at very short intervals (continuous)

Versioning

Versioning is simply retaining older version of files (or backups) rather than overwriting them during the backup/sync process. You can generally define how many versions to keep, but if you choose to cull older files, this is till not true backup which again, is an immutable copy of your data, drives, or system.

Optical discs

Every backup program supports hard drives, but as obsolete as they may seem, DVDs and Blu-Ray discs are great archive media. If you’re worried about optical media’s reliability, M-Disc claims its discs are reliable for a thousand years, backed up by Department of Defense testing.

Online storage (cloud) support

An offsite copy of your data is a hedge against physical disasters such as theft, flood, fire, and power surges. Online storage services are a great way to meet that need. Some backup software will let you back up to Dropbox, Google Drive, OneDrive, Amazon S3 and compatible, etc. however Cloud Managers can serve as a workaround with backup programs that don’t. The downside to cloud storage is relatively slow performance. Keep a local backup for faster restores.

Network access

Backing up to other computers or NAS boxes on your network or in remote locations (say your parent’s or children’s house) is another way of safeguarding your data via a physically remote copy. If you use network storage, it can also be handy to back them up to you local system.

FTP/SFTP can be used for offsite, while SMB (Windows and most OS’s) and AFP (Apple) are good for other PCs or NAS on your local network. Network support is not universal, and some backup programs allow you to back up to, but not from network shares. Just be careful in the way you expose your computers on the Internet.

Real-time backup

Real-time backup means that files are backed up whenever they change, usually upon creation or save. It’s handy for keeping an immediately available backup of rapidly changing data sets. For less volatile data sets, scheduled backups will do just fine.

Continuous backup

Continuous simply means backing up on a tight schedule, generally every few minutes, rather than in real time, daily, weekly, or monthly. Use continuous backup for rapidly changing data sets where transfer rates are too slow, or computing power too precious for real-time backup.

Performance concerns

Most backups proceed in the background or during dead time, so performance isn’t a huge issue in the consumer space. However, if you’re backing up multiple machines, backing up to multiple destinations, or dealing with very large data sets, speed will be a consideration. That said, backup speed is highly dependent upon the hardware and transport technology in use.

Further reading: Check out PCWorld’s roundup of best external drives for recommendations on reliable storage options — an important component in a comprehensive backup strategy.

FAQ


1.

What is the best Windows backup software?

The best Windows backup software is Easeus Todo Backup 2025. It has everything PCWorld expects to see in a top product: A polished interface, intuitive functionality, a comprehensive approach to backing up data including imaging, file backup, sync, and disaster recovery. And most important, it’s reliable! Todo Backup also offers the option of a perpetual license or a subscription model, the latter of which can be augmented with affordable cloud storage.

2.

What is the best free Windows backup software?

It turns out that PCWorld’s favorite for-pay backup software, Easeus Todo Backup 2025, also offers a surprisingly robust free version. It matches its paid counterpart in basics such as imaging, file backup, sync, and, most especially — disaster recovery. It also features the same eminently user-friendly interface. As with most backup freeware, you will be nagged to upgrade, and Easeus’s optional cloud storage, which is surprisingly affordable, is only available at the subscription tier.

3.

Will backup software slow down my computer?

Backup software typically runs in the background or during dead time, so given even moderately modern hardware, you shouldn’t notice any decrease in performance. Most programs let you throttle the backup process if you do notice a slowdown.

4.

Does Windows Backup and Restore (Windows 7) save everything?

Yes, by default, Backup and Restore (Windows 7) saves everything on your system disk (all the partitions, including hidden ones) in what’s known as an image file that would be suitable for disaster recovery if Windows Recovery Drive and Rescue disk were reliable. News bulletin — they aren’t.

Hence, we only recommend this program for creating highly compatible VHD/VHDX images of your data drives and partitions which can be mounted as virtual drives and browsed using nothing but Windows Explorer.

5.

What’s the difference between Google Drive, Dropbox, OneDrive, etc. and backup software?

Google Drive, Dropbox, and OneDrive are what’s known as cloud storage, or online storage. They create a local virtual drive that you can drag files to, and which is eventually synced to the cloud as time allows. They also provide a Web portal where you can manage your files remotely.

However, by default these services sync changes in the data across all devices. True backups should be immutable snapshots that may be added to but not changed. Some services offer versioning (keeping older files, and adding new ones), which creates a close approximation to backup.

Cloud backup services (distinct from those mentioned above) offer many, though not all, of the benefits of Windows backup software. This is generally done with local client software that offers just basic functions like file backup and sync. You can learn more about these in our roundup of best cloud backup services.

6.

How often should backups be scheduled?

Ideally, as often as your data changes. If you are working on an important project or have work that you absolutely cannot afford to lose, you should consider real time (as data changes) or continuous (very short intervals). Hourly, daily, or longer intervals will be fine for the average user. All file backups should be augmented by weekly or monthly system backups.

7.

Can I back up files to and from my cloud storage?

Until a few years ago, most Windows backup software was restricted to making local backups — i.e., to another drive, external or internal, connected to your system. There were of course services such as Mozy that had their own backup clients, but that’s covered in our online backup roundup. Here we’re talking just plain backup programs.

The situation is improving rapidly, and many backup software vendors are adding online storage services as destinations for their backups.

If your favorite backup program doesn’t support cloud storage directly, a cloud storage manager that integrates online storage services into File Explorer can make online backup possible with just about any backup app.

8.

What’s the difference between full, differential, and incremental backup?

A full backup is a backup of all your data, regardless of how new or old it is. A differential backup is all the data that’s changed since your last full backup. An incremental backup is all the data that’s changed since any your original full and/or the last differential/incremental backup. Differential and incremental backups require a initial full backup to be restored.

Differential backups require more time to create than incremental backups, but are quicker to restore since you only need the latest iteration. Differential backups can grow to be quite large if you don’t perform full backups very often.

Incremental backups take less time to produce and are smaller, but take longer to restore as all of them created since the last full backup must be restored in the order in which they were created.

9.

What’s the difference between image backup, system backup, and file backup?

An image is low-level backup of all the sectors (including “empty” sectors if you wish) contained by a disk or partition, regardless of their pertinence to your files. It’s basically fool-proof in terms of accidentally overlooking important data.

A system backup is an disk image backup of all the partitions on your system drive. This includes several that are hidden, i.e., not enumerated as drive letters by the operating system. A system backup might also include other drives, but must contain the OS drive.

A file backup is a high-level backup of data read via the operating system’s file system. Most often this is data, but may include all the files on a drive.

10.

What should I back up?

In truth, it’s only your essential personal data that must absolutely, positively, 100% be backed up. Once the family pictures or your work-in-progress are trashed with no backup, there’s no way back other than an expensive recovery service, and even that’s not guaranteed if the physical media is unreadable.

On the other hand, a system backup is exceedingly handy for getting you back up to speed with minimal hassle. It returns your system to exactly where you were at the time of the backup: OS, program, updates, upgrades, settings, data are all back in a relative blink of the eye.

But it’s not essential. While reinstalling operating systems, drivers, and programs, as well as adjusting settings require more effort, you can then recover your data if that’s all you backed up. See the first paragraph.

Want your photos to survive for decades? A digital archivist explains what to do

29 September 2026 at 07:00

Some people spend most of their digital lives on social media and save almost nothing with the intention of preserving it for the future. They might share photos and videos on Instagram or send them via a messaging app, but it’s all ephemeral. If they ever want to keep something, they might order prints or a photo book.

Most people, however, have a great deal in their digital collections – both on their computers and on their smartphones – that they hope will remain, if not forever, then at least indefinitely. Family photos, holiday videos, scanned documents, old newspapers, and letters are among the files that I want to remain even after I’ve kicked the bucket.

But unlike books and physical photo albums, it’s by no means a given that digital files will still be there or accessible in 25, 50, or 100 years’ time, just as you can’t leave a photo album out on the balcony and expect it to be intact many years later. The moral of the story is this: You need to look after your digital assets. But how to do that in a way that’s sustainable in the long term isn’t always obvious.

How do the experts who work on preserving all kinds of information for the future go about it, and do they have any advice for us mere mortals?

Ina-Maria Jansson
Ina-Maria Jansson.

Privat

Ina-Maria Jansson is a researcher and archivist at Uppsala University Library and works on the preservation of personal digital archives. She says there is one important thing to bear in mind for anyone who wants to ensure that their loved ones will be able to enjoy their digital collections, apart from the choice of storage media, file formats, and how backups should be handled:

Document everything! What seems obvious to you may be a jungle for your next of kin. Write down exactly what’s in your digital archive and create an index to describe the contents of your folders and files. Label hard drives and other storage media with their contents. Let those who will be your next of kin know that the documentation and files exist, and make it easy for them to find the documentation.

She notes that a common mistake many private individuals make is failing to consider that their next of kin may not share the same keen interest in those files.

Digital material requires active stewardship that is difficult to avoid, regardless of the measures taken. Will children and grandchildren have the time and energy to take on digital stewardship when they are busy living their own lives? To make things easier, it’s important to explain the content as clearly as possible – what it is and why it’s important. If possible, it’s best to go through the content with your children and grandchildren well in advance, so that they know it exists.

Fotoalbum
A photo album you can hold in your hands.
Pavel Danilyuk

Put it in writing

Ina-Maria Jansson wants to make a case for physical or analogue archiving of the most important photos and documents.

We humans are often more primitive than we might like to admit. If something isn’t visible, it doesn’t exist! Because digital photos and videos don’t take up the same physical space and aren’t as easy to look at as a box of photo albums, they’re easily forgotten during a move or when clearing out an estate.

Creating physical copies of photos and other items you really cherish makes them both more durable – as long as you look after them properly! – and easier for your loved ones to preserve and appreciate.

For those who want peace of mind, I’d advise against storing things digitally unless you’re certain that a surviving relative will want to continue managing the digital collection. Instead, select paper copies of your best photographs and place them in acid-free paper sleeves along with details.

16-millimetersfilm
Analogue film lasts longer than most digital storage media.
Sami Türk

Ina-Maria Jansson acknowledges that video is trickier than photographs. But if you have some truly cherished films that you think your descendants might actually enjoy, there is a way to preserve them in analogue format, too.

You can turn to a company that can transfer the digital films to analogue 16-millimeter film. Many of us may have spent a great deal of money digitizing older films, so it might seem strange that I’m suggesting the opposite, but you’ll understand the point better if you think in terms of a working copy and an archive copy.

In that case, the digital file can serve as a working copy, while the analogue film takes on the role of an archive copy. Under optimal conditions – kept cool, preferably frozen in a metal container – analogue film has a lifespan of up to 500 years! Compare that to a hard drive, which might last for 10 years.

Of course, many people have far too many photos to be able to print them all out. Even if you weed out all the dull ones, you can still benefit from a certain degree of analogue archiving.

Even if the files themselves are stored on your computer, you can create a folder, a keepsake box, or a notebook where you can collect prints and information about your digital legacy.

Sortera på datorn
Programs such as Lightroom help you sort through and organise all your photos and videos.
Jamies X Co

An ongoing task

When I ask Ina-Maria Jansson whether there is any technology that makes it possible to copy important files once and then leave them untouched for many years without risking their loss, the short answer is: no.

Sooner or later, some sort of action will need to be taken. You can choose storage media with the longest possible lifespan, but sooner or later they’ll need to be reviewed. Files on a standard home computer with a hard drive may last a few years, but they’re also exposed to both physical threats such as a house fire and digital threats such as viruses and bit rot. They’re also susceptible to other issues such as the file format becoming unreadable.

Technologies are currently under development that make it possible to store data for thousands or even millions of years, in extreme environments. A couple of years ago, researchers at the University of Southampton demonstrated five-dimensional memory crystals in which data is stored using extremely fast laser beams inside quartz crystals. The largest prototype can store 360 TB with an estimated lifespan of several billion years, and the researchers have, among other things, stored a human’s complete DNA code in a mountain cavern in Austria called Memory of Mankind.

Tidskriftssamlare
Organization and order.
Zulfugar Karimov

For consumers, media can last for several decades if stored correctly. The problem is that it’s impossible to know when they’ll start deteriorating. That’s why it’s important to go through and check everything that’s still working and can be read, so that any incipient faults can be detected while the files are still in a position to be recovered.

For most private individuals, Ina-Maria Jansson says that cloud storage is the best option.

You don’t need to worry about having lots of backups stored in different places, as long as you make sure that your accounts and login details are properly documented. It’s also a good idea to make sure any fees for the cloud service continue to be paid even if the account holder passes away suddenly. Inform your next of kin that the account exists and make it easy for them to find your login details and documentation.

Bit rot and other threats

As Ina-Maria Jansson mentions, files stored on physical storage media in your home can be lost in many ways. Hard drives, SSDs, and Blu-Ray discs can be lost in a fire or flood. If the files are stored on a hard drive or SSD connected to a computer, they may be lost due to malware (like ransomware) or accidentally overwritten. The files may also become corrupted over time, a phenomenon known as bit rot.

If you’ve worked with old data, then you’ve probably experienced this phenomenon. Files that are a few years old can suddenly become corrupted or impossible to open, even though everything appears to be working correctly. Sometimes, it’s possible to repair them, but not always. This could be due to natural wear and tear on the storage medium itself or digital circuits losing their power. Sometimes, it’s caused by read and write errors in the software. It’s also a risk that arises when files are copied or moved and the entire file isn’t transferred.

Hårddisk
Hard drives do not last forever.
William Warby

She says there’s software that actively combats bit rot by periodically scanning all files and using checksums to verify that no files have been altered. It only takes a single 1 or 0 to be changed for the checksums to fail to match, at which point the system can repair the file in question. This is called scrubbing and is a feature of, among others, the ZFS file system, which you can use on NAS devices, for example.

Other threats to be aware of include software updates required to open the files and ensuring you have digital playback equipment compatible with your storage medium. A lot can happen in a decade, and your files are meant to last considerably longer than that, aren’t they?

Choose open file formats

When it comes to long-term storage, Ina-Maria Jansson says that researchers usually distinguish between archive formats and everyday formats. The latter are formats that are practical to use in day-to-day life and to share with family and friends. Archive formats, on the other hand, are chosen because they are most likely to remain usable many years from now. They are open formats such as PDF, TIFF, and PNG.

Pdf
The PDF format is one of the recommended archival formats.
Jan Novaczek

When it comes to video, things are once again a little more complicated. The National Archives recommends Matroska files (.mkv) with video in FFV1 format and audio in LPCM format for long-term preservation. However, uncompressed high-definition video takes up an incredible amount of space, so the vast majority of people have to make do with a compressed format.

The most common compressed format today is H.264, but it’s not entirely open. A modern alternative is AV1, which is both open and free from royalties and other restrictions, so it’s highly likely that software capable of playing such files will be available in the future.

But, as I said, as long as we haven’t sorted out a long-term digital preservation solution that can be passed to future generations, the file format doesn’t really matter that much.

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