I pick the 'make bootable' and 'copy mbr' options when I clone the drive to the other drive. I pull the old primary drive out (i have drive bays) and reboot with the other drive, but it tells me no MBR was found.
I'm cloning from an 'extended' partition on a 500G hard drive split in half, and it's Windows 7. The primary partition has another Windows 7, which I've delete most of the files it would allow me to delete off it (for other reasons I won't discuss), so is most likely not even bootable at this point, but it comes up as an OS to boot to when I start my computer (even though I don't pick it anymore). Now that I've cloned the Windows 7 OS sitting on the extended partion of the 500G drive to a 200G drive, if I leave the other drive in the top bay (200G in the 2nd bay with a newly cloned copy of the Windows 7 OS from the 2nd partion of the big drive), my boot manager comes up with 3 picks: 2 Windows 7 and 1 Windows Vista. Funny it calls my new Windows 7 clone a Vista, but I'll assume that is because 14 came out before knowing what Windows 7 was, and there is no patch for that yet.
At any rate, I can boot by picking it from the list of 3 OSs to boot from (leaving the big drive in), but that concerns me that I can't boot off that other drive when it is the 'only' drive in my system, telling me I don't have an MBR (even though I picked it when copying the drive), because my ultimate goal is to blow away that 2nd partition on the 500G drive and make one big partition, and copy the 200G back to the 500G.
So why is my drive not booting up, do you suppose? Both are SATA (it's possible the 200 is 150/mb, but that shouldn't matter, it's just slow is all).