Windows Shadow Copy or Volume Snapshot service VSS is a backup of your NTFS volume or drive. Windows automatically creates a system snapshot of the NTFS drive when there is patch update or changes to the system. There are also ways to set-up VSS on NTFS drivers manually or periodic schedule.
Use the command to view a list of shadow copies for a specific drive, c: drive in this case.
vssadmin list shadowsTo delete the existing Shadow Copy or Snapshot:
1. Open command prompt in administrator mode by type
CMD in the search box, right click CMD program and open as administrator
2. Type this command
vssadmin delete shadows /for=c: /all and hit enter
3. Choose Y on the confirmation and hit enter. A message will display showing how many VSS copies deleted.

The above will delete all Shadow Copies on the C drive.
Use this command to delete oldest Shadow Copies only:
vssadmin delete shadows /for=c: /oldestUse this command to create a new shadow copy for a volume.
vssadmin create shadow /for=c: