Can PGP universal server skip encrypt Whole Disk and just use for portable disk?

My company evlauate a VM product that have built-in encryption within VM boundary for desktop virtualization.  However, we still need to block  USB storage device to prevent user copying corporate data  within VM to external USB drive from to host.

Is it possible to disable encrypt whole disk feature and only enable PGP portable disk function?

Version:  PGP Univeral server  3.1.2

                PGP desktop 10.1.2

Thanks,

Jimmy