How to Check Volume Shadow Copy Services Driver State

If you encounter errors during backup initialization of Microsoft Server 2008 or 2008 R2, or Small Business Server (SBS) 2011, you may have misconfigured or disabled Volume Shadow Copy Services (VSS) drivers. Microsoft provides a command-line tool to verify the state of the VSS writers. To utilize this tool, open a command prompt on the Windows Server, and enter:  vssadmin list writers

Following is an example using this tool to check driver status:

C:\>vssadmin list writers

vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool (C) Copyright 2001 Microsoft Corp. 

Writer name: 'System Writer'

Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}

Writer Instance Id: {449e12cf-6b8f-4d75-a821-bc869d6612c4}

State: [1] Failed

Last error: No error

Writer name: 'SqlServerWriter'

Writer Id: {a65faa63-5ea8-4ebc-9dbd-a0c4db26912a}

Writer Instance Id: {de3b2861-77f6-43f8-8619-64dc9ea2fbcf}

State: [1] Stable

Last error: No error

Writer name: 'MSDEWriter'

Writer Id: {f8544ac1-0611-4fa5-b04b-f7ee00b03277}

Writer Instance Id: {9036fdfa-05ef-4f7d-9c2f-84fa2f06560a}

State: [1] Stable

Last error: No error

Writer name: 'WMI Writer'

Writer Id: {a6ad56c2-b509-4e6c-bb19-49d8f43532f0}

Writer Instance Id: {f9f92826-a3d4-486c-ade3-a4201deb8ad2}

State: [7] Failed

Last error: No error

If the output of this command contains writers with a state that is not Stable, you must restart the VSS service Volume Shadow Copy Services. If you continue to see this error in reports and agent logs even after restarting the services, register your VSS drivers use the following instructions:

• Windows Server 2008 and Windows Server 2008 R2 – VSS drivers on Windows Server 2008 and 2008 R2 can normally be reset by restarting the Services from the Management Console based on the Microsoft Knowledgebase solution No VSS writers are listed when you run vssadmin list writers on Windows Server 2008. 

• Small Business Server (SBS) 2011 – Refer to the Microsoft Knowledgebase solution You May Get VSS Warnings in the Application Event Log of SBS 2011 Standard.

  Important
  Restarting VSS on Windows 2008 can cause unexpected behavior. Verify that all necessary writers (e.g., Hyper-V or Exchange) have restarted or data objects may not be detected or backed up. It is recommended that you reboot the Server in lieu of restarting the VSS writer components listed below, and verify that all appropriate Microsoft updates are installed. Restarting VSS on SBS 2011 may cause post installation errors to display. See the Microsoft Knowledgebase solution Windows SBS 2011 Standard Known Post Installation Event Log Errors and Warnings for additional information.

If you determine that restarting Services is appropriate for your environment, complete the following steps:

1. Log in to the system, and click Start.
2. Enter services.msc in the Start Search box, and press Enter.
3. In the Services window, right-click each of the following services individually, and then click Restart:
   
   • COM+ Event System
   • Volume Shadow Copy
4. Close the Services window.
5. Open an elevated command prompt, enter:
   vssadmin list writers
6. Press Enter.
7. Verify that the VSS writers are listed.