How to check a backup before you need to restore it
Quick answer: A successful copy notification is useful, but opening a restored copy tells you more. Test a small, representative sample in a separate folder and record both the result and the location of the backup.
Choose what a useful recovery means
Start with a simple question: if the original folder disappeared, what would you need to resume your work? For a household folder, that might include a PDF, a spreadsheet and photographs. For a creative project, it might also include linked images and application-specific files.
The exercise below checks ordinary personal files. It is not a full system recovery test and does not prove that every item in a large backup is healthy. For work-managed devices, follow your organization’s recovery procedure.
Prepare a safe test destination
- Identify the actual backup source and the date of the version you want to test.
- Choose a few files with different formats, including a recently changed document.
- Create an empty folder named
restore-check-2026-10-04, using your own test date. - Restore or copy the sample from the backup into that folder. Do not restore over your working originals.
- Open each recovered file in its intended application and inspect useful content.
If your backup application offers a separate-location restore option, use that documented option. If it only offers an overwrite operation and you are unsure of the consequences, stop and consult its help first.
Check more than whether the icon appears
| Sample | Useful check |
|---|---|
| Page count, first and last page, readable text. | |
| Spreadsheet | Expected sheets, recent entries and formulas. |
| Photo | Full-size image rather than only a thumbnail. |
| Project folder | Required companion files and linked assets. |
Make a short recovery record
Write down the test date, backup location, version date, restored sample and result. Add any missing dependency, such as an application needed to open a project. Keep instructions accessible without relying solely on the device you are protecting. Do not record passwords in a plain-text recovery note.
A useful result is specific: “Restored the October spreadsheet and opened all three sheets” tells you more than “backup seems fine”. If a file fails, try another known version while preserving the failing copy for investigation.
Repeat when something important changes
A new backup service, replacement drive or different computer can change the recovery path. Repeat a small test after such changes and periodically according to the importance of the files. CISA advises testing that backups can restore data; the sample workflow here turns that principle into a manageable personal check.
CISA joint advisory: backup and recovery guidance · Name recovery copies clearly