SIRIS, ALTO and NAS: Datto Windows Agent: Error: "Snapshot not in a good state - State 5 Error 0x00000028"



When you start a backup by using the Datto Windows Agent, you see a generic "Critical backup failure during data transfer" error in the device GUI. In the agent logs, you see, "Snapshot not in a good state - State 5 Error 0x00000028."


  • Datto Windows Agent 2.1 and above


The Copy on Write (COW) file for one or more volumes is highly fragmented, causing the backup to fail.

You'll see the following error in the Agent Logs from the Protect tab of the Datto device GUI:

Snapshot not in a good state - State 5 Error 0x00000028. Deleting snapshot set 801ade94-1ece-42b4-af67-dca42b2c9a6a


Confirm the fragmented volume 

1. Pause backups for the agent and cancel any active backup jobs

2. Download and extract the Microsoft program Contig from the Sysinternals website (external link).

3. Open an elevated command prompt and navigate to the download location of Contig.

4. Run the following commands to check the COW (.ctl) file for fragmentation:

sc stop dattofsf
contig.exe -a C:\datto.ctl
sc start dattofsf     

5. Check the output for the value ${file} is in ${x} fragments. Example output:

C:\Users\Administrator\Downloads\Contig>Contig.exe -a C:\datto.ctl

Contig v1.8 - Contig
Copyright (C) 2001-2016 Mark Russinovich

C:\datto.ctl is in 10130 fragments

     Number of files processed:      1
     Number unsuccessfully procesed: 0
     Average fragmentation       : 10130 frags/file

6. Repeat steps one through five for each volume included in the backup.

If you find disk fragmentation

Perform the following steps for any COW file that shows 1000 fragments or more.

1. Uninstall the Datto Windows Agent from the protected machine.

2. Defragment each volume where COW fragmentation was high.

3. Reinstall the Datto Windows Agent.

4. Start a new backup and monitor for recurrence.

If you do not find disk fragmentation

Contact Datto Technical Support for assistance.

Was this article helpful?

1 out of 1 found this helpful

You must sign in before voting on this article.

Want to talk about it? Have a feature request?

Head on over to our Datto Community Forum or the Datto Community Online.

For more Business Management resources, see the Datto RMM Online Help and the Autotask PSA Online Help .

Still have questions? Get live help.

Datto Homepage