The untested backup problem

Most small businesses have some form of backup. Most have never tested whether those backups can actually be restored. This is a critical gap: a backup is only valuable when you need to recover from it, and discovering that recovery doesn’t work in the middle of a data loss event is the worst possible time.

The statistics are uncomfortable: a meaningful percentage of backup restorations fail when actually attempted. Drive errors, software version mismatches, incomplete backups, and corrupted files are all common causes. The only way to know your backup works is to test it.

What “testing a backup” actually means

Testing a backup means actually restoring from it — not just confirming that the backup ran successfully. A backup software reporting “backup completed” means the data was copied. It doesn’t mean the data can be recovered.

A full test: restore the backup to a test machine or a test folder and verify the files are complete, readable, and functional.

For file backups: Restore a sample of files — at least 5–10% of the total backed-up data, including large files and files of different types. Open several and verify they’re not corrupted.

For full system backups (imaging): Restore the image to a spare machine or a virtual machine and verify the system boots and functions normally.

For cloud backups: Use the provider’s restore interface (not just file download) to restore a folder to a test location.

How often to test

  • File backups: Test quarterly. Restore a random sample of files and verify them.
  • Full system images: Test every 6 months. This is more time-intensive but critical for businesses that would need a full system restore to recover from a ransomware attack.
  • Cloud backups: Test after any major change to what’s being backed up (new software installed, file structure changed, new users added).

Building the habit

Put backup tests on the calendar as recurring events with a specific owner. A backup test that isn’t scheduled doesn’t get done. The test takes 30–60 minutes per quarter and is one of the highest-value IT activities a small business can perform.