WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
SolarWinds Backup - Modern server backup software
TreeSize - TreeSize tells you where precious disk space has gone to.
Zerto - Virtual replication & recovery solution
SpaceSniffer - SpaceSniffer is a freeWare (donations are welcome) and portable tool application that lets you understand how folders and files are structured on your disks.
ShadowProtect SPX - ShadowProtect backup and disaster recovery software ensures on-prem business systems and data are fully protected and always available.