Acronis Cyber Protect: how to fix corrupted archives in network locations

Acronis Cyber Protect: how to fix corrupted archives in network locations


When backing up to NAS or a network folder using Version 12 backup format, the archive may become corrupted and operations with the archive will fail with "data is corrupted: CRC mismatch or internal data structures mismatch".

Such errors are usually caused by hardware problems or file system issues on the backup destination.

Starting from Acronis Cyber Protect Cloud C20.12 (Build 26077) and Acronis Cyber Protect 15 Update 2 (Build 27009), you can create a system variable that enables the system to scan for the last good state of backup archive and attempt to repair it. After the repair, the backup archive should be accessible again.

This solution only works for network locations.


Perform the following steps on the Agent machine that created the faulty backup:

  1. Press Win+R, type sysdm.cpl into the input field and press Ok.
  2. System properties window opens. Go to the Advanced tab and click on Environment variables
  3. In System variables section, click New
  4. Create a new variable with the following parameters:
    • Variable name: ARCHIVE3_AUTO_REPAIR
    • Variable value: 1
  5. Save changes and close System properties window
  6. In Protection Console, go to Backup Storage tab, select the archive that causes the error, and click Show backups. While accessing the backup, Agent will attempt to find the last good state and fix the archive.