A fatal error occurred during a Windows Server Backup snap-in (Wbadmin.msc) operation.
wbadmin delete catalog
from https://social.technet.microsoft.com/Forums/en-US/c3ec1565-56dd-4b2c-be75-65cd8a2a2f65/a-fatal-error-occurred-during-a-windows-server-backup-snapin-wbadminmsc-operation?forum=windowsbackup