The shutdown blocker avoids broken backups due to users doing a shutdown or reboot during backup.

During a running backup, the tray application detects any shutdown or reboot and blocks this. Some applications may have already been closed until the dialog appears but the backup continues. 

A dialog pops up and notifies the user that a backup is running: 

The shutdown is now already stopped. The user can cancel or run a shutdown again. 

Using the client software on Windows Computers