Backing up properly, and why sync is not a backup
Cloud sync protects you from a broken laptop. It does not protect you from a mistake, and the difference is the whole point of backing up.
By Hasnain Butt Akhtar, founder and developer ·
Most people believe they are backed up because their files are in OneDrive, Google Drive or Dropbox. Those services are genuinely useful and they will save you if your laptop is stolen. They will not save you from the far more common way people lose files, which is doing something to them and not noticing for a fortnight.
The difference in one sentence
Sync copies your current files to another place. Backup keeps earlier versions of them.
That distinction is everything. If you delete a folder, sync obediently deletes it everywhere. If a file becomes corrupted, sync copies the corrupted version over the good one. If ransomware encrypts your documents, sync uploads the encrypted versions and overwrites what was there. In each case the service worked exactly as designed, and your files are gone from every device at once.
A backup keeps yesterday's copy, and last week's, so a mistake made today is recoverable.
Most sync services do have some version history, which softens this. It is usually limited to thirty days, often applies only to files rather than whole deleted folders, and the recovery process is awkward when you need to restore thousands of files at once. It is a safety net rather than a backup, and it is worth knowing which one you are relying on.
How files are actually lost
It helps to design around the real causes rather than the dramatic ones.
| How it happens | Does sync save you? | What does |
|---|---|---|
| Deleted by accident, noticed months later | No | Backup with long version history |
| Overwrote the good version with a bad edit | Sometimes, within the retention window | Versioned backup |
| Drive fails | Yes | Sync or backup, either works |
| Laptop stolen or lost | Yes | Sync or offsite backup |
| Ransomware | No, it syncs the damage | An offline copy the malware cannot reach |
| Fire, flood or theft of the whole room | Yes, if the copy is elsewhere | An offsite copy |
| The service closes your account | No | A copy you physically hold |
Look down that middle column. Sync handles hardware failure and theft well, and handles nothing else. Those are real risks, but they are not the common ones.
The three copy rule
The standard advice, and it has lasted because it is simple: three copies of anything you care about, on two different kinds of storage, with one of them somewhere else.
In practice, for a normal household, that looks like this:
- The working copy. The files on your computer, the ones you use every day. This is copy one.
- A local backup. An external drive that keeps versions, not just a mirror. This is what you restore from when you delete something by accident, and it is fast because the drive is right there. This is copy two, on a different kind of storage.
- An offsite copy. Either a cloud backup service, or a second external drive that lives somewhere other than your home and gets swapped every month or two. This is copy three, and it is the one that survives a fire or a burglary.
Windows includes File History, which handles the second copy without extra software. Turn it on in Settings under System and Storage, point it at an external drive, and it keeps versions of your libraries automatically. It is not the most capable tool available, but it is already there and it is far better than nothing.
The detail that catches people out
An external drive left permanently plugged in is only half a backup. Ransomware encrypts attached drives too, and a power surge takes out whatever is connected. If you use a single external drive, unplug it between backups. It is a small habit that changes what the backup actually protects against.
Check what is included. Backup tools usually cover your user folders by default and miss things stored elsewhere. Game saves, email stored locally, browser bookmarks, licence files, and anything you keep on a second drive are commonly left out. Spend five minutes confirming what is in the set rather than finding out later.
Encrypt anything that leaves the house. A drive kept at a relative's house or in a desk drawer at work will eventually be lost or looked at. Windows can encrypt an external drive with BitLocker in a couple of clicks, and it costs you nothing in convenience once it is set up.
Test it, or you do not have one
This is the step everyone skips, and it is the one that separates a backup from a folder of hope.
Once a backup is running, pick a file at random and restore it somewhere else. Open it. Confirm it is the right version and the content is intact. Do this when you set the backup up, and again every few months.
People discover broken backups at the worst possible moment: the drive was full for eight months, the scheduled task stopped after an update, the folder they assumed was included never was. All of those are obvious the first time you try a restore, and invisible until then.
A setup that is enough for most people
If you want a straightforward answer rather than a menu:
Keep working files where you already keep them. Turn on File History pointed at an external drive, and unplug that drive when it is not backing up. Keep your cloud sync running for convenience and for the phone photos it collects. Add one cloud backup service, or a second external drive kept elsewhere, for the offsite copy. Then restore one file to prove the whole thing works.
That covers accidental deletion, a bad edit, drive failure, theft, ransomware and fire, in about an hour of setup and a few pounds a month. The photographs alone are usually worth considerably more than that, and unlike almost everything else on a computer, they cannot be replaced at any price.