Running DiskLock (version 4.5.1) produces a message that "DiskLock does not support this system. It is too new." It suggests contacting PowerOn software for an update, but their Web site does not mention that one is available, or even being developed. The implication is that you had beeter unprotect ALL DiskLock protected disks BEFORE you install OS9, or you will not be able to run DiskLock to unprotect them afterwards.