What limitations are there to performing successive snapshots?
Before a new snapshot can be initiated, the interface needs to be torn down by calling BackupShutdown. You can confirm that BackupShutdown has been successfully called by increasing logging on the Exchange writer and examining the application event log for event 9648 (Exchange VSS Shapshot backup has been shutdown successfully). If BackupShutdown is not called, or was not successful, you will most likely see the following error in your application event log.
