In a recent post I outlined how I created a rudimentary backup solution using DiskShadow and Rsync. On one particular 2008R2 server, I struck a problem with the DiskShadow script. It would error when it tried to create the shadow copy.

After some searching, I discovered that there were 2 VSS Providers installed. At command line, type:

vssadmin list providers

or at a DiskShadow prompt:

list providers

One provider was the Microsoft one and the other was a Acronis one. As soon as I specified the Microsoft provider in the DiskShadow script, the script worked and created the shadow copy. However, I did not really want to have to specify the provider (although its probably better practice).

Coincidentally, I also had Acronis Backup and Recovery 10 (ABR) installed on this server. I cannot remember why now but I would always get an Acronis error whenever I logged on to the server. Which I had been meaning to look at for a long time. My initial thought was, remove ABR and it will remove the VSS provider. 

Imagine my surprise when I tried to remove ABR through ‘Programs and Features’ and got another error preventing removal. After some more searching, I found the ABR Cleanup Utility here:

http://kb.acronis.com/content/6177

This successfully removed all ABR programs but not the VSS provider. Therefore, I manually removed it from the registry using information on these pages:

http://forum.acronis.com/forum/27806

http://forum.acronis.com/forum/11602

After a restart, my DiskShadow script worked fine without having to specify the VSS provider.

Thanks again to all those that blog and post.