I bought Acronis True Image 10. My purpose was to "clone" my hard drive to keep a back up in case the primary died. (I was recently burned by not having a back up drive). My computer uses XP Home Edition. I had a 40 Gig hard drive (WD) in the computer and I bought the same drive but in 80 Gig as the new one. I put the new drive in with the old with a new cable and everything set as cable select. I loaded True Image 10 and used the "Clone" feature. It seemed to work like a charm. When it was done, I rebooted and it started right up. My inspection revealed that my new "cloned" larger drive was now the primary "C" drive and my old smaller drive was now the "F" drive. Therefore the cloning worked since the new larger "cloned" drive was "C" and the machine had booted off it. Now, I wanted to test my old (now "F" drive) to make sure that if the new larger "cloned" drive failed, I was still all set. I tried to boot off the old "F" drive by switching the cable connections. No go. Then I changed the boot priority in the BIOS. No go. I have been reading some of the posts here and it seems there is an issue that my leaving "both" drives hooked up when I rebooted the first time might do something to disable the MBR? in one of the drives. Questions: 1) Why did my new bigger "cloned" drive become the new "C" drive? (Not that I am complaining) 2) Did my initial booting up with both drives connected cause this problem? 3) How do I correct it and achieve my purpose of a back up drive? 4) Can I do the cloning again, this time from the new bigger "cloned" drive to the old smaller drive (essentially reversing the process) and then disconnecting one of the drives when I do the intial reboot? 4a) Would there be a problem now that I would be cloning a bigger drive onto a smaller drive? ( I only have about 20 Gigs consumed the 80 Gig drive) 4b) Does it matter which drive I disconnect on the initial reboot? 5) Is there another way to accomplish my task? Whew! Thanks for your time, Al Tierney P.S.: I know enough about this to be dangerous, but am not a PC pro.