Every - and I do mean EVERY - backup I have ever made using Retrospect is unreadable. That's going all the way back to 1998. Apparently no version of Retrospect is able to read an encrypted backup produced by a previous version of Retrospect. "Unknown media" is the error message. Dantz's reply is the usual "oh, it shouldn't be doing that - there must be something wrong with your machine..." All eight of them? I have eight Macs from the latest Pro to a vintage grape iMac and none of them can read any Retrospect backup produced by a previous version of Retrospect. Avoid this software, well, unless you want to make backups you can't actually read...