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[V7] ISSUE: Unexpected error querying for the IVssWriterCallback interface. Access is denied (Hyper-V VM backup / restore)

Article ID: 5256
Reviewed: 2017-07-17

Product Version:
AhsayOBM / AhsayOBR: to 7.x
OS: Windows

ATTENTION 1st January, 2022: v7 officially End-of-Life [details]


When performing a backup or restore of a Hyper-V guest virtual machine, the following error message is logged in the Window Event Viewer:

Volume Shadow Copy Service error: Unexpected error querying for the IVssWriterCallback interface. hr = 0x80070005, Access is denied

Although, there are VSS related errors the Hyper-V guest backup / restore jobs was completed successfully without any warnings or errors.


This VSS related error is caused by a Window VSS configuration issue.

Note: This error does not affect the integrity of the guest virtual machine backup or restore job.


To resolve this problem:

  1. Open dcomcnfg.exe, expand Component Service, Computers, then right click My Computer and choose Properties.

  2. Select the Com Security tab then click Edit Default... under Access Permissions.

  3. Click Add..., then enter Network Service in the Enter the object names to select text box, and click OK.

  4. Confirm that only Local Access is selected, then click OK.

  5. Restart the Hyper-V host machine(s) for the settings to take effect.


Hyper-V, guest VM, VSS, access denied, network service

public/5256_issue/volume_shadow_copy_service_error/unexpected_error_querying_for_the_ivsswritercallback_interface._hr_0x80070005_access_is_denied._error_is_shown_in_windows_event_viewer_for_hyper-v_backup_restore_job.txt · Last modified: 2021/12/16 05:26 by anna.olalia

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