Fix VSS Meta Data is Missing or Corrupt

Rectifying the "Meta collection during application-aware backup failed. VSS metadata is missing or corrupt. The file is corrupted." error with Acronis Backup for VMWare

I got this information from a friendly bloke at Acronis support, thought I'd share the information here.

The Error Message

If your Acronis backups are failing with the following messages shown in the logs, the steps shown below should help you out. They came from a helpful gentleman at Acronis support.

Meta collection during application-aware backup failed.
VSS metadata is missing or corrupt.
The file is corrupted.

Steps to Resolve

You must uninstall VMWare tools (do this through 'Uninstall Programs' in the Control Panel) on the machine which the backup is failing for. If the if you're having difficulty identifying which machine it is, take a look in the logs around the time you are experiencing the errors and you should be able to determine which machine is having the VSS errors by the last machine that was being quiesced at the time of the failure.

When the VMWare tools uninstall is complete, it will be worth rebooting the system.

Once the machine has come back up, initiate another installation of VMWare tools, this time selecting the Full Install option. Run through the installation as normal from inside the virtual machine.

You can also download the following files from this link ( however they are downloadable directly from the below list:

  1. VCBSnapshotProvider.dll (146.5 K)
  2. VCBRequestor.dll (86.5 K)
  3. ComReg.exe (74.5 K)

Then create a folder with name "VSS" in the following location and copy the VCBSnapshotProvider.dll and VCBRequestor.dll files to this location:

C:\Program Files\VMware\VMware Tools\Drivers\

Then copy the file ComReg.exe file to the following locations:



C:\Program Files\VMware\VMware Tools\

Finally, load up services.msc and set the following services to automatic and ensure they are started:

  • Distributed Transaction Coordinator Service
  • Com+ System Application Service

You should now be able to kick off the Acronis backup job and see it running through successfully.