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ISSUE: Cannot start shadow copy (VSS_E_WRITERERROR_NONRETRYABLE) (VSS Event 8193 - Access is denied)

Article ID: 8094
Reviewed: 10/11/2020

Product Version:
AhsayOBM: or above
OS: Windows

Problem Description

When performing a MS SQL database backup job, the following backup error is received in the backup report:

No. Type Timestamp Log
* ... ... ...
* info ... [Start] Backing up database...
* erro YYYY/MM/DD hh:mm:ss Cannot start shadow copy, reason =The writer operation failed because of an error that might
recur if another shadow copy is created. (VSS_E_WRITERERROR_NONRETRYABLE)
* ... ... ...
At the same time the following errors appear in Windows Application Event log:

Log Name: Application
Source: VSS
Date: DD/MM/YYYY h:mm:ss
Event ID: 8193
Task Category: None
Level: Error
Keywords: Classic
User: N/A Computer: Computer_name Description:
Volume Shadow Copy Service error: Unexpected error calling routine RegOpenKeyExW(-2147483646,SYSTEM\CurrentControlSet\Services\VSS\Diag,...). hr = 0x80070005, Access is denied.

Note: This issue will often occur after installing the DHCP role on the MS SQL server.


The error can be cause by installation of the DHCP role on the SQL server, resulting in the Network Service account losing the permissions on the registry key


The problem is related to the installation of the VSS module DHCP Jet Writer, which is responsible for correct shadow copy creation of the DHCP service. This VSS module changes permissions on the specified registry key during the installation.


To resolve the issue, assign Full Control permissions to the Network Service account for the registry key:

  1. Open Registry Editor from the Windows Start menu.

  2. Browse to:


  3. Right click on Diag, then click Permissions option in the context menu.

  4. Find Network Service in the list and assign the Full Control permissions.

  5. Click OK, then restart the server afterward.


ms, sql, dhcp, vss, nonretryable, denied, deny, mssql

public/8094_issue/vss_e_writererror_access_is_denied.txt · Last modified: 2020/11/18 17:31 by edward.chan