You can manage the Volume Shadow Copy service using the Vssadmin command-line tool from an elevated command prompt. You can use this tool to run the following commands:
Vssadmin List Providers Lists registered Volume Shadow Copy providers. Windows Vista includes Software Shadow Copy Provider 1.0.
Vssadmin List Shadows Lists existing volume shadow copies, the time the shadow copy was created, and its location.
Vssadmin List ShadowStorage Lists the volume shadow storage space currently in use, the space that is reserved for future use (labeled as allocated), and the maximum space that might be dedicated. This space is used to store changes while a shadow copy is active. The following sample output was generated using a computer that currently had about 3GB of files stored in a shadow copy, but that might allocate as much as 6.4GB.
Vssadmin List Volumes Lists volumes that are eligible for shadow copies.
Vssadmin List Writers Lists shadow copy writers, which support communicating with the Volume Shadow Copy service to ensure that files are captured in a consistent state. By default, subscribed writers include an operating system writer, a registry writer, a WMI writer, and a search service writer, among others. SQL Server also provides a Volume Shadow Copy writer.
Vssadmin Resize ShadowStorage Resizes Volume Shadow Copy storage. You can use this command to increase the maximum space that might be used by Volume Shadow Copy. Typically, this is unnecessary. However, if you discover that backups are failing on a computer because of an extremely high volume of changes during a backup, and Vssadmin List ShadowStorage reveals that the used Shadow Copy Storage space is at the maximum, you might be able to resolve the problem by manually increasing the maximum size.