Troubleshooting System State backups (using wsb plugin)

This FAQ can be updated each time new errors with known fixes or better troubleshooting techniques are developed.

Troubleshooting system state backup on server 2008 can be time consuming and there are various factors which can cause wsb system state backup to fail within the Scomis remote backup service .

First of all, check that the disk on the drive which the system state backup is running on has free space. Open the backupclient console, go to Tools, Plugins, System State / WSB. Note the drive it’s backing up to. ie C:\

Check that there is at least 15GB (ideally much more) as the WindowsImageBackup folder needs around 10-15GB for the vhd image file.

Once fixed, or if the above is irrelevant, proceed with the below troubleshooting –

Checking vss writers are all up and running

A good process to follow is opening an elevated command prompt

C:\Windows\System32>vssadmin list writers

Check to see if any of the writers listed are showing as Timed out, failed, waiting for completion etc. They should all show as Stable and No Error.


Writer name: ‘System Writer’
Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}
Writer Instance Id: {85177af5-14dd-45bd-b410-6e6be412b5f2}
State: [1] Stable
Last error: No error

If there are any writers which have failed or are awaiting completion, identify these and restart the corresponding service as per the table below

VSS Writer Service Name Service Display Name
ASR Writer VSS Volume Shadow Copy
BITS Writer BITS Background Intelligent Transfer Service
COM+ REGDB Writer VSS Volume Shadow Copy
IIS Config Writer AppHostSvc Application Host Helper Service
IIS Metabase Writer IISADMIN IIS Admin Service
Microsoft Exchange Writer MSExchangeIS Microsoft Exchange Information Store
Microsoft Hyper-V VSS Writer vmms Hyper-V Virtual Machine Management
Registry Writer VSS Volume Shadow Copy
Shadow Copy Optimization Writer VSS Volume Shadow Copy
SQLServerWriter SQLWriter SQL Server VSS Writer
System Writer CryptSvc Cryptographic Services
WMI Writer Winmgmt Windows Management Instrumentation

If the VSS writers continue to cause trouble, a scheduled reboot of the server is recommended so all services are restarted and this can fix the issue.

Other things to check –

Registry entry to enable system state backups to critical volumes

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To enable the system state backup files to be targeted to critical volumes, you must set the value of the AllowSSBToAnyVolume registry entry under the following registry subkey:


Set the value of this entry as follows:

Name: AllowSSBToAnyVolume
Data type: DWORD
Value data: 1
Check disk space
In the backup console, go to Tools, Plugins, System State (using wsb) and find out where the system state backup is pointing to. ie C:\ will mean it’s creating the system state backup in C:\WindowsImageBackup
Check the disk space of the selected volume. Typically you will need at least 15GB of free space for the windowsimagebackup folder. If low on disk space, free up some space if you know there are some no longer needed files which can be deleted, or move the system state backup to another volume if available by changing the path in the backup software as above and selecting the relevant volume ie E:\. Delete the existing windowsimagebackup folder on the drive which is nearly full.
Check event logs
Go to server manager and check the Server Manager\Diagnostics\Event Viewer\Windows Logs\Application for any errors.
Look at the application log to find out when the system state backup failed and check for any corresponding event warnings or errors during the same time.
This may identify what service or area needs investigating.
Other kb articles to check –
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