SD sandbox won't boot

[moctar]

Hi all,

I've searched the excellent forum here but cannot find a solution to my problem.

I have 2 internal drives, one of which boots to OS X 10.5.5. I have used SuperDuper! to designate the other internal drive as a Sandbox. I have done a copy for "Sandbox - shared users and applications" with "Erase, then copy", and it proceeds fine, giving all three green checkmarks in the copy process (including "make sandbox bootable" and "restore spotlight...")

Problem is, when I restart the system, hit F12 to enter boot options, if I choose the drive where the Sandbox volume is located, it just freezes.

Both drives use GUID partition table map schemes, and I have successfully used the Sandbox drive previously as a bootable volume into Vista.

So, I used to be able to choose between a) OS X on drive 1, and b) Vista on drive 2, upon boot. Now, I want to choose between a) OS X on drive 1, and b) Sandbox on drive 2.

What am I missing to make the Sandbox bootable???

Thanks for any support!!