Hyper-V backup fails: "Signaling bad state returned for writer [Microsoft Hyper-V VSS Writer]"

Article ID: HPV0007 When backing up Hyper-V virtual machines, the backup job fails and the Hyper-V writer is left in a bad state.


The host is Microsoft Hyper-V Server 2012 and the guest OS for the virtual machines is Windows Server 2012, Windows Server 2008, or Windows Vista or later.

The following errors appear in the vsbkp.log file.

Signaling bad state returned for writer [Microsoft Hyper-V VSS Writer] engaged in backup.
The job will go to pending state and will be retried.


A Windows Server 2012 host is missing necessary updates that provide a new version of the Integration Components.


  1. Apply the updates from the following link to the Microsoft Hyper-V Server 2012:

    Windows 8 and Windows Server 2012 update rollup: November 2012 (Windows Update – KB2770917)

  2. Restart the server after applying this update.
  3. Deploy the new version of the Integration Components to the guest OS on each Hyper-V virtual machine.