Data loss – What should you do?

It only takes an accidental click, a system crash or a cyberattack for important data to be deleted. However, if the appropriate precautions have been taken, the damage caused by losing data can often be limited and lost data restored.

Important data can be lost without warning: one wrong click, a system crash, a virus, a defective device or a software error can suddenly cause photos, documents or entire project folders to disappear. If this happens to you, it is important to remain calm and take things step by step, as data can often be at least partially recovered.

Initial steps after data loss

Stay calm and stop using the affected device or drive. New data can permanently overwrite deleted files. Try to identify the cause: was the data deleted deliberately by malware, accidentally by a user, or was there a system crash or technical defect? Before using any additional software, check the most obvious recovery options first, such as the Recycle Bin or Trash, and any existing cloud or automatic backup copies.

Data destroyed by malware

If you suspect that data has been deliberately deleted or made unusable, the NCSC recommends consulting an IT specialist. If no backup is available, or if the backup was also damaged in the incident, unfortunately there is very little chance of recovering the data. If extortion is also involved, the NCSC strongly recommends filing a criminal complaint with the police.

Data recovery after accidental deletion or system errors

Depending on the device and operating system, various recovery options are available:

Windows devices

  • Check the Recycle Bin for accidentally deleted files.
  • Use File History or restore points to restore earlier versions of files.
  • Check the OneDrive Recycle Bin. Deleted files are kept there for up to 30 days.
  • There are also programs (some of them free of charge) that you can use to try to recover deleted files. However, caution is needed here too: fraudulent programs also exist. Read other people's reviews beforehand. Always install such programs on a drive other than the one affected by the incident.

MacOS devices

  • Check the Trash for accidentally deleted files.
  • Use Time Machine to restore files from an earlier backup.
  • Check the iCloud Recently Deleted folder. Deleted files are kept there for up to 30 days.

iPhone

  • Check the Recently Deleted folder in the Photos app. Deleted images are kept there for 30 days.
  • Restore the device from an iCloud backup if one is available. Please note that this may overwrite more recent data.

Android

  • Check Google Drive and Google Photos for files that still exist or are in the bin.
  • Check the device’s own bin in the Gallery app.
  • There are apps that may be able to recover deleted files. However, complete recovery is not guaranteed. However, caution is needed here too: fraudulent programs also exist. Read about other people's experiences beforehand.

Recovering data from the cloud

Many people automatically back up their photos, documents or contacts using services such as Google Drive, iCloud, OneDrive or Dropbox. Cloud storage services are convenient and reliable, but data stored in the cloud is not immune to loss. Common causes of data loss include accidental deletion, synchronisation errors, expired retention periods or a blocked user account. In many cloud services, deleted files are stored in the bin for only a limited time.

  • Check the bin of the relevant service, as many files can be restored within 30 days.
  • Use version history to restore earlier versions of files.
  • Check device backups.
  • Check whether you have a complete backup from before the data was lost.
  • If you have lost access to your account or have unexpectedly lost data, the provider's customer support team may be able to help.

If these methods do not produce results, or if the hardware is damaged, it is advisable to contact a specialist data recovery service. These companies have professional tools and procedures for recovering data, even from physically damaged storage media

Further information

Backups: Cybersecurity is S-U-P-E-R.ch (German, French and Italian)