Forum Discussion
there is no problem with VSS, I perform this test successfully
vssadmin Add ShadowStorage /For=C: /On=D: /MaxSize=900MB
(C) Copyright 2001-2005 Microsoft Corp.
Successfully added the shadow copy storage association
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C:\Users\Admin>vssadmin list shadowstorage
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.
Shadow Copy Storage association
For volume: (\\?\Volume{7240e843-914a-11e2-bb8c-806e6f6e6963}\)\\?\Volume{724
0e843-914a-11e2-bb8c-806e6f6e6963}\
Shadow Copy Storage volume: (\\?\Volume{7240e843-914a-11e2-bb8c-806e6f6e6963}
\)\\?\Volume{7240e843-914a-11e2-bb8c-806e6f6e6963}\
Used Shadow Copy Storage space: 0 B (0%)
Allocated Shadow Copy Storage space: 0 B (0%)
Maximum Shadow Copy Storage space: UNBOUNDED (100%)
Shadow Copy Storage association
For volume: (C:)\\?\Volume{7240e844-914a-11e2-bb8c-806e6f6e6963}\
Shadow Copy Storage volume: (D:)\\?\Volume{3df823db-9166-11e2-b277-6c3be5a607
c7}\
Used Shadow Copy Storage space: 0 B (0%)
Allocated Shadow Copy Storage space: 0 B (0%)
Maximum Shadow Copy Storage space: 900 MB (0%)
==================================================================================
C:\Users\Admin>vssadmin create shadow /for=C:
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.
Successfully created shadow copy for 'C:\'
Shadow Copy ID: {6e074368-ded5-4aa8-9a21-bdb48de7f497}
Shadow Copy Volume Name: \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy477
C:\Users\Admin>
C:\Users\Admin>vssadmin list shadows
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.
Contents of shadow copy set ID: {5f60055e-0248-49f5-811c-4478ed193641}
Contained 1 shadow copies at creation time: 11/4/2016 5:06:13 AM
Shadow Copy ID: {6e074368-ded5-4aa8-9a21-bdb48de7f497}
Original Volume: (C:)\\?\Volume{7240e844-914a-11e2-bb8c-806e6f6e6963}\
Shadow Copy Volume: \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy477
Originating Machine: SONEP-NBU02
Service Machine: SONEP-NBU02
Provider: 'Microsoft Software Shadow Copy provider 1.0'
Type: ClientAccessible
Attributes: Persistent, Client-accessible, No auto release, No writers
Differential
C:\Users\Admin>
C:\Users\Admin>vssadmin delete shadows /for=C:
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.
Do you really want to delete 1 shadow copies (Y/N): [N]? Y
Successfully deleted 1 shadow copies.
C:\Users\Admin>
Your vssadmin example shows you have 900MB snapshot space for C:\. On an active system, 900 MB is tiny. Be aware that if your copy-on-write snapshot runs out of space, the OS deletes the snapshot right out from under bpbkar. That's probably not what's happening here, but we had a pair of cases a couple of years ago where it did happen. One customer had just what you have, 900 MB snapshot space for the drive that held all their Exchange databases.
Your bpbkar snippet is so short, all I see is G:\, not C:\. What drives are you backing up? What drives is it failing on? Can we see more of the bpbkar log, with the logging level turned up?