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Volume GUID mismatch / Set dependency chain GUID mismatch



Backups fail with error code:


Figure 1: Set dependency chain GUID mismatch  

Possible Causes

  • ShadowSnap is unable to continue to the next incremental because the StorageCraft journal numbers became out of sync.
  • Volumes of the drives are in states that ShadowSnap cannot read properly.
  • The agent was rebooted in the middle of a backup
  • A backup was interrupted mid-transfer before completion due to a dirty shutdown of the ShadowSnap services on the protected system
  • Separately created ShadowProtect jobs are configured on the target agent, interfering with the incremental tracker used by ShadowSnap.
  • A RoundTrip drive may improperly interrupt the backups and journaling numbers. This can result in all agents requiring diff-merges.
    • RoundTrip error codes and messages may vary in appearance, including "invalid data format," "GUID mismatch," and write errors.  


  • Make sure that the protected server's ShadowSnap software is updated to the latest version.
  • Check to see if any ShadowProtect backup jobs are present, as shown in Figure 2. If there are, disable or remove the jobs.

Figure 2: ShadowProtect backup jobs


  • ShadowSnap and ShadowProtect use the same incremental tracker. After you confirm that the ShadowSnap Agent is updated to the latest version, force a differential merge through the Protect → Configure Agent Settings → Advanced section of the Datto appliance's Remote Web, as shown in Figure 3.

Figure 3: Force Differential Merge

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