Volume Shadow Copy Error 0xffffffff - catastrophic failure

Error code


Applies to



Applies to BackupAssist v4 to v7


This article is specific to Server 2003 and NTBackup. These are no longer supported in the latest version of BackupAssist. This article is not actively maintained and updated.

This error indicates that the backup process is having difficulties with backing up Open Files. This is due to a problem with the Volume Shadow Copy Service in Windows that is utilized to perform backups of any open files or files that are in use at the time of the backup process.


Resolution 1 - Check Volume Shadow Copy Service

Make sure that the Microsoft Software Shadow Copy Provider service is started and set to automatic startup type.

  1. Go to Start > Control Panel > Administrative Tools > Services
  2. Find the Volume Shadow Copy service.
  3. Right click on the service and go to properties.
  4. In that screen, you can set the startup type and start the service.

Resolution 2 - Hotfixes available from Microsoft directly

It has been confirmed that the following hotfixes have resolved this error once they are installed onto the faulting machine:

Resolution 3 - Find which component of VSS is at failing

Run the following command from a command-line interface: vssadmin list writers

This will list the vss writers present on your system. Please look for the any that are displayed with errors as this will indicate what part of the snapshot caused the error.

The VSS service within Windows writes a lot of information to the Event Viewer, which is a great resource for finding the root cause of this error. Check the Event Viewer by selecting on Start > Run > Eventvwr. See if there are any specific VSS or SPP warnings or errors being generated from the system during the backup process. To learn more, see this video about these specific event logs: https://www.youtube.com/watch?v=76u-MML-h9w.

Also make sure that the Volume Shadow Copy Service is not disabled, and that no other 3rd party VSS providers are interfering with the backup. (Control Panel > Administrative tools > Services).

Resolution 4 - Check the Backup User Identity's permissions

Check that your Backup User Identity has been set and has the required access. To view your current Backup User Identity, select the Settings tab > Backup User Identity and you'll see the following dialogue box appear.

Backup User Identity

Note: For BackupAssist 10.4.2 and earlier, the Backup User Identity is used for all backup jobs and the account may have been created with custom access levels. For 10.4.3 and later, a Backup User Identity is only required for Jobs that have a NAS destination or the SQL add-on, and in these cases, the Backup User Identity should be a member of the Administrators group.

What to check

  • For BackupAssist 10.4.2 or earlier - check that the account is still selected, enabled and has the required access.
  • For BackupAssist 10.4.3 and later, check that the account is still selected, enabled and a member of the administrators group.
  • To check the permissions properly, you can log into the backup server using the Backup User Identity account and check that you can read and write to the backup destination without any authentication requests or errors.
  • If backup account's password is changed in Windows, it will need to be changed in BackupAssist.

To learn more, see Backup User Identity

Last updated


Further assistance

8th June 2017

23rd Aug 2007

BackupAssist Support page