The required step is to verify that the third-party OST target supports Accelerator with VMware-type policies in the Hardware Compatibility List. Cohesity NetBackup documentation states that Accelerator for virtual machines uses VMware Changed Block Tracking (CBT) to identify changes inside the virtual machine, not the Windows NTFS or ReFS change journal. The same VMware Accelerator requirements topic lists supported disk storage destinations and includes qualified third-party OpenStorage devices, then specifically instructs administrators to verify Accelerator support for the storage unit in the NetBackup hardware compatibility list for supported OST vendors. It also warns that if the storage unit does not support Accelerator, the backup can fail with messages such as the storage server type not supporting accelerator backup. The HCL further identifies Accelerator with VMware-type policies as a distinct OpenStorage supported-functionality entry, meaning generic OST support is not sufficient; the vendor/device must support the VMware Accelerator capability. (Veritas Download) Option A applies to file-system Accelerator behavior for Windows clients, not VMware image-level backups. Option C is not mandatory for the first successful VMware backup. Option D is incorrect because VMware Accelerator does not require manually creating a client track log.