Here's the scenario. It's a bit complicated, so try to bear with me.... I have a 15" MBP from 08 running Snow Leopard. It's running a bit slow these days and I upgraded to a new 17" i7 MBP running Lion. I've done all the upgrades and firmware updates (on both systems.) The Lion machine is running great. However, I teach classes that use Adobe Connect, and Connect will not run properly in Lion (did all the updates, tech support, etc). So, not wanting to use the older 15" to hold my classes, I partitioned the hard drive of the newer mac for a bootable Snow Leopard install. Now here's the snag. I have an installation DVD and a thumb drive both bootable with Snow Leopard, and both will mount, but the new mac will not boot from either of them (the older one does). When trying to run the installation straight from the mounted drives, I get an error: "You have to Install Mac OS X.app 23.1." I've searched for such a thing and have come up empty. So, I've tried using the various networking solutions, but they are not working. The partition on the new mac is shared and mounts on the old one, but is not selectable when running the installer. I've tried using "Remote Install" from the old to the new, but that requires option-rebooting the new mac and choosing the disk, but the partition does not have a system in it yet. Migration Assistant does not help as it does not copy the Operating System. I have Time Machine backups on an external drive, but the restoring I need to do doesn't work (Snow Leopard restore file is not an option from the Lion machine to the partition). So..... I'm currently doing a "hard" copy directly from the backups. I'm not hopeful this will work, and I'd really rather do a clean install on the partition. Is there something I'm missing? Is there a reason why this is so difficult, if not impossible?