Manually provisioned desktop pools are typically used when the desktops are created outside the Horizon View environment using tools such as vSphere or an array-based virtual machine cloning tool. These manually provisioned desktops must be available in vCenter in order for them to be added to the manually provisioned desktop pool.
Prior to creating the manually provisioned desktop pool, at least one supported virtual machine with the Horizon View agent installed must be available within vCenter. This desktop must not be assigned to any existing desktop pools, as it will be added to the new manually provisioned desktop pool during the pool-creation process.