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[V8] ISSUE: [VSSDatabaseExpt] VSS_E_UNEXPECTED_PROVIDER_ERROR (MS Exchange database backup)

Article ID: 8071
Reviewed: 2020-04-09

Product Version:
AhsayOBM: to 8.x
OS: Windows

Problem Description

When performing either a scheduled or manual MS Exchange database backup job. 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 Exchange version is updated to the latest service pack / rollup.
  2. The MS Exchange Server has been rebooted.
  3. The VSS writers have 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 "Microsoft Exchange Writer" 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: 'Microsoft Exchange Writer'
    Writer Id: {76fe1ac4-15f7-4bcd-987e-8e1acb462fb7}
    Writer Instance Id: {2e8409fa-1dd8-483c-ba95-5c9277be0509}
    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 Exchange 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 Exchange 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, Microsoft Exchange Writer

public/8071_issue/exchange_database_backup_vssdatabaseexpt_e_unexpected_provider_error.txt · Last modified: 2021/12/14 00:52 by anna.olalia

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