Trying to reinstall Parallels after a year away from the machine. Get this error code when trying to install on the same partition as Boot Camp Error: PRL_ERR_DISK_INVALID_BLOCKSIZE (0x80021009) Path: '/Users/Office2/Parallels/My Boot Camp.pvm/Hitachi HDE721064SLA360 (disk2).hdd' The partition is NTFS format? Any ideas? Bit more info. Installing to Windows 10 on a Mac Pro 5.1. Windows install as well as Boot Camp drivers are all up to date. Hitachi drive is a platter drive. Thanks a lot.