Microsoft Volume Shadow Copy Service (VSS) is necessary for application-aware processing, which ensures that applications like Microsoft SQL Server and Exchange can be properly quiesced for backups. Using Microsoft VSS, you can create a consistent backup of your SQL server with the ability to restore to a specific point in time. Additionally, VSS integration is needed if you want Veeam Backup & Replication to truncate logs for applications like Exchange Server to manage their size and ensure they do not consume too much disk space. Therefore, to achieve point-in-time restore for Microsoft SQL Server and to truncate backup logs for Exchange server, Microsoft VSS should be used instead of VMware quiescence.