I am trying to backup data from a windows 7 Home premium hard drive to another windows 7 home premium hard drive data partition using a usb caddy/enclosure. Both hard drives currently boot when connected to the motherboard of my pc and both OS partition and data partition are available. However when I put one or other hard drive into the enclosure, Windows 7 HP only shows one drive and says I need to format the drive. I have tried connecting the enclosure to a notebook with Windows starter installed and although I still cannot access the OS partition the data partition is available. The Netbook does not have a big enough hard drive to back up the data so I really need to find a way for Windows 7 HP to access the data. Please advise if I can do anything to fix this issue without formatting or using recovery software.