Almost everyone who loses data was fairly sure they were covered. The gap is usually the same one: what they had was a sync, or a copy, or a very old external drive in a drawer — none of which is a backup when it matters.
The rule that survives everything: 3-2-1
Three copies of anything you cannot bear to lose, on two different kinds of storage, with one of them somewhere else entirely. It sounds like an IT slogan until you notice what it defends against: the drawer copy handles a failed drive, and the off-site copy handles the fire, the flood and the burglary that took both computer and drive together.
Why OneDrive, iCloud and Dropbox are not enough on their own
Sync services mirror your mistakes. Delete a folder, or let ransomware encrypt one, and the change is faithfully copied to the cloud within seconds. They are genuinely useful — most keep deleted files and older versions for around 30 days, which has saved plenty of people — but that window is short, and it only covers the folders you actually sync. Anything outside them is unprotected.
The 20-minute setup that covers most people
Layer one, automatic and local: buy an external drive at least twice the size of your computer's storage. On Windows, use File History (Settings, then System, then Storage, then Backup options) or the built-in system image tool. On a Mac, plug the drive in and say yes when it offers Time Machine. Both then run themselves.
Layer two, automatic and off-site: a cloud backup service that backs up the whole machine continuously, or at minimum your cloud drive syncing the documents and photos folders. This is the copy that survives the house.
Layer three, the one people skip: your phone. Photos of your children, of receipts, of the boiler serial number. Check that iCloud Photos or Google Photos backup is actually switched on and not paused for lack of storage space — a paused backup is the commonest phone data loss there is.
Ransomware changes one thing
Modern ransomware deliberately hunts for connected backup drives and encrypts them too. So keep at least one copy disconnected — an external drive you plug in weekly and unplug afterwards is unglamorous and completely effective — or use a backup service with versioning, so you can roll back to before the infection.
A backup you have never restored is a rumour
Once a year, open the backup and pull one real file out of it. That five-minute test catches the drive that quietly stopped backing up in March, which is the single most common way "I had a backup" turns into "I had a backup until March."
What to protect first, if you do nothing else today
Photos and videos. Documents and anything tax-related. The business file — accounting data especially. Password manager exports and recovery codes. Programs can be reinstalled and Windows can be reloaded; these cannot be recreated at any price. If you are here because something is already missing, stop and read what to do about lost files before you touch the computer again.
Want it set up once, correctly?
A verified technician can configure automatic local and off-site backups over a screen-share, test the restore with you, and be gone in under an hour.
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