Can I restore anonymized e-mail addresses?

Can I restore anonymized e-mail addresses?

No, it is not possible to restore anonymized email addresses. Once an address has been anonymized, all associated personal data is irreversibly removed.

Why is a recovery not possible?

  1. Anonymization is a final process: By converting the email address into an irreversible string (hash), the original data becomes unrecognizable.
  2. Technical implementation: The hash algorithm used (SHA-256) makes it impossible to restore the original email address from the anonymized form.
  3. Data protection & GDPR: Anonymization serves data protection purposes and ensures that no personal data remains.
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Can I restore an address if it was not anonymized?

Yes, as long as the unsubscription data has not been anonymized, an address can be restored with the full subscriber data in the original subscriber list. The following applies:
  1. If the address has been unsubscribed from all lists, it will be restored with a new subscriber ID (subscriber statistics will be lost).
  2. If the address was only unsubscribed from one of several lists, the original subscriber ID remains, and the affiliation with the old subscriber list is restored.
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How can I prevent important data from being accidentally anonymized?

  1. Carefully check before anonymization whether the data may still be needed.
  2. Create regular backups of your subscriber data in case you need unsubscription data for internal evaluations.
Once anonymized, addresses are permanently deleted – recovery is no longer possible.