Start with these three steps
Write down the exact operation
Record the tool, command or menu used, the selected disk or volume and whether it completed. Keep screenshots or repair paperwork if already available.
Stop setup and new writes
Avoid installing apps, creating more accounts or copying files onto the erased storage. Record everything already done after the erase.
Check backups elsewhere
Use a working device to inspect Time Machine, cloud originals, exports and other computers. Keep those sources separate from the erased iMac.
Identify the action before choosing a response
Apple’s Erase All Content and Settings feature removes user data, settings and apps while keeping the installed operating system. Disk Utility has a different erase workflow. Ask whether the operation targeted the internal disk, one volume or an external archive.
If someone else prepared the iMac for sale or repair, obtain their exact description. A working setup screen is not evidence that an old user folder is waiting to be undeleted. Likewise, the word formatted on a job sheet is insufficient to predict recovery.
Sources: [1] Apple Support [2] Apple Support
Completed secure erasure can be final
Apple describes deletion of the necessary encryption material on Apple silicon and T2 systems as making a volume cryptographically inaccessible. In that situation, readable flash contents and knowledge of the old password do not recreate the destroyed keys.
Do not rely on a promise to undo every factory reset. Ask a provider which specific evidence would make this case recoverable and whether it is proposing to retrieve an independent backup instead. Backup recovery can be useful, but it should be identified clearly.
Sources: [3] Apple Platform Security
An older format still needs a careful assessment
On an older iMac, a disk format may leave a different recovery question from a hardware-backed secure erase. The outcome depends on the actual storage, operation and subsequent activity. Neither the computer’s age nor the speed of the format demonstrates that the former files survived.
If the procedure was a Fusion rebuild, retain all original devices and disclose that operation. Apple warns that its reconstruction process deletes the member-drive data. Do not attempt another rebuild or reinstall as an experiment while an assessment is being considered.
Sources: [2] Apple Support [4] Apple Support
Rebuild your working data from verified copies
List the newest useful copy of each important category: documents, photo originals, financial records and active projects. An existing Time Machine backup can support a broader migration, while cloud and exported copies may need to be checked separately.
If residual-data assessment is still planned, restore onto different storage or a different Mac. Verify recovered material before resuming normal work on the source. Keep notes about any gaps so an assessor can focus on the missing files rather than recovering duplicates you already have.
Sources: [5] Apple Support [6] Apple Support
A realistic view of recovery
- A completed cryptographic erase cannot be reversed by an ordinary recovery scan.
- Overwritten or internally cleared content cannot be recreated merely by repairing a filesystem or changing a login password.
Your questions, answered
Can my old FileVault password reverse an erase?
Should I reinstall macOS to see whether anything comes back?
Is recovery impossible after every format?
Need help with the original iMac?
Describe the model, what happened and which data matters. Data Recovery Lab NZ is an external specialist; ask it to confirm the assessment route for your exact device.
Sources & further reading
Primary and specialist guidance checked 27 October 2026. Features and instructions depend on the model and operating system.