Windows Server Backup - delete all backups

Hi,

got a Windows Server 2008R2 running with Windows Server Backup,

and now the Backup mmc shows "Total Backups: 94 Copies" (that were the old Backups which arent available anymore)

Total backups should be 0

All Backups

Total backups: 93 copies

Latest copy: 26/05/2014

Oldest copy 13/05/2010

Is there any way to delete those? I tried to reinstall the Feature but didnt work either.

VSS admin:

PS C:\> vssadmin list providers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Provider name: 'Microsoft Software Shadow Copy provider 1.0'
   Provider type: System
   Provider Id: {b5946137-7b9f-4925-af80-51abd60b20d5}
   Version: 1.0.0.7

PS C:\> vssadmin list shadows
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

No items found that satisfy the query.
PS C:\> 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: (C:)\\?\Volume{5fabbfa0-7e17-11de-89ab-806e6f6e6963}\
   Shadow Copy Storage volume: (C:)\\?\Volume{5fabbfa0-7e17-11de-89ab-806e6f6e6963}\
   Used Shadow Copy Storage space: 0 B (0%)
   Allocated Shadow Copy Storage space: 0 B (0%)
   Maximum Shadow Copy Storage space: 6.833 GB (10%)

Shadow Copy Storage association
   For volume: (D:)\\?\Volume{d5cf2101-d91f-11de-9833-0026558367b7}\
   Shadow Copy Storage volume: (D:)\\?\Volume{d5cf2101-d91f-11de-9833-0026558367b7}\
   Used Shadow Copy Storage space: 0 B (0%)
   Allocated Shadow Copy Storage space: 0 B (0%)
   Maximum Shadow Copy Storage space: 54.68 GB (4%)