Backstory: I used earlier versions of PM a long time ago - maybe that is the reason for my confusion. This was what I wanted to do: Exchange my current SSD for a bigger one. The bad news: For space reasons I cannot connect my new (bigger) SSD, and have my old SSD and my hard drive connected at the same time. So, my current partition setup is this: SSD: Bootable MBR + OS partition C: Hard disk: Data partition E: (Optical drive: D: ) What I intended to do was this: 1. Shrink and move E: to the end of the hard drive. 2. Create a new partition at the start of the hard drive. 3. Copy my OS partition (i.e. the complete content of C: ) to the hard drive. 4. Make the hard drive bootable. 5. Unplug the old SSD, plugin the new SSD 6. Migrate the OS partition from the hard drive to the new SSD. Step 1, shrinking and moving up E: was no problem. Step 2, creating a new (physical, non-virtual) partition in the now empty space at the start of the hard drive also worked fine. Step 3, copy the OS partition C: onto the newly created partition on the hard drive, also went well. Although I was confused that the copy was done while the OS was running; I had expected it to happen outside of the OS after a reboot, like the partitioning tasks. Here I am stuck at Step 4 - making the hard drive bootable. PM12 has an option "Copying Tasks -> Migrate OS", but according to the warning I got, all data on the hard drive would be erased by that action. Not just the data on the target partition, but all data on the hard drive - which obviously would be bad for my data partition E: How can I safely move my Windows 7 OS partition from the SSD to the harddrive, without losing the hard disk's content? And make Windows 7 bootable on the hard drive? Maybe I was too naive in step 3 (copying the OS partition to the hard drive), and making the hard drive bootable would not help me anyway? Thanks a lot for your help!