This error occurs when one of the VSS writers is not in a working state and causes the snapshot process to fail.
The error's known causes and resolutions are described below.
Many backup solutions have their own proprietary snapshot manager which can cause conflicts with other backup solutions installed on the system.
If you have (or had) more than one backup program installed on your system, disable/uninstall all of the programs except for BackupAssist, and run the backup job again.
It is best practice to only have one backup solution installed at any one time.
You should also run a registry cleaner after the other backup solutions have been uninstalled: http://www.backupassist.com/blog/support/how-to-resolve-a-ba910-volume-shadow-copy-error-0x80004230/.
If the reason for the error is a failing VSS writer, it’s recommended to find which one is causing the issue.
To do this, open an elevated command prompt and run the following command: vssadmin list writers
This will provide an output of all VSS writers known to Windows on that machine. Look specifically for the Last error detail and anything that does not show No Error is most likely to be the cause of the error.
VSS can write additional information to the event logs of your system which will provide information to help resolve the issue.
Open Event Viewer by clicking on Start > Run > Eventvwr to see if there are any specific VSS warnings or errors being generated from the system during the backup process. You will specifically want to look at the Application and System logs.
This is generated because the SQL writer has conflicts with the SharePoint VSS writer.
It is known that removing the GUID entry from the following registry key resolves this error:
HKEY_LOCAL_MACHINE/ SOFTWARE/ MICROSOFT/ MICROSOFT SQL SERVER/ SHAREPOINT/ SQLSERVERAGENT
Stopping the SQL VSS Writer Service can also resolve this error.
To do this, browse to Administrative Tools > Services and find SQL Server VSS Writer in the list. Once located, click on Stop to the left hand side of the Services screen.
This error is generated if there is an issue with the file Sqlvdi.dll on the system.
Microsoft outline how to resolve this in their KB: https://support.microsoft.com/en-us/kb/830575.
BA954 Volume Shadow Copy Error 0x800423f4 - writer error: non retryable