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ISSUE: [VSSDatabaseExpt] VSS_E_UNEXPECTED_PROVIDER_ERROR (MS SQL database backup in VSS mode)

Article ID: 8072
Reviewed: 09/04/2020

Product Version:
AhsayOBM: or above
OS: Windows

Problem Description

When performing either a scheduled or manual MS SQL Server database backup job in VSS backup mode. The following backup error are received in the backup report:

No. Type Timestamp Log
* info ... Using Temporary Directory ...
* erro YYYY/MM/DD hh:mm:ss Cannot start shadow copy, reason =VSS_E_UNEXPECTED_PROVIDER_ERROR
* ... ... ...
The backup error persists even after the following actions have been performed.

  1. The MS SQL Server version is updated to the latest service pack / rollup
  2. The MS SQL Server Server has been rebooted
  3. The VSS writers has been re-registered using the %OBM_Install_home%\bin\RegisterVSS.bat
Checking the status of the VSS writers using the vssadmin list writers command shows the 'SqlServerWriter' is still in a "Failed" state.


C:\WINDOWS\system32>vssadmin list writers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2013 Microsoft Corp.

Writer name: 'System Writer'
    Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}
    Writer Instance Id: {a2f2507d-b348-493a-9685-da3f20959e9d}
    State: [1] Stable
    Last error: No error

Writer name:'SqlServerWriter'
    Writer Id: {a65faa63-5ea8-4ebc-9dbd-a0c4db26912a}
    Writer Instance Id: {3de4f842-4d57-4198-9949-3b3f8c2629dc}
    State: [7] Failed
    Last error: No error

Writer name: 'FRS Writer'
    Writer Id: {d76f5a28-3092-4589-ba48-2958fb88ce29}
    Writer Instance Id: {d35e3901-f9b9-4fa6-86af-36b8a4872933}
    State: [1] Stable
    Last error: No error


This issue can occur if there is not enough space on the SQL server to create a VSS snapshot of the database. In other words, the maximum size of the shadow storage area is too small.


To resolve this issue, consider to resize the maximum shadow storage area on the MS SQL server.

Refer to the following Microsoft Document for details on how to resize the shadow storage area:


UNEXPECTED, PROVIDER_ERROR, VSSDatabaseExpt, shadow storage, resize, VSS Writer, SqlServerWriter

public/8072_issue/mssql_server_database_backup_vssdatabaseexpt_e_unexpected_provider_error.txt · Last modified: 2020/11/17 23:48 by edward.chan