I got this error in Windows 7 after resizing/moving the OS partition using gparted. Well i used the win 7 boot disk to try the "Repair my Computer." option. Well when i got there the OS wouldnt even show up. After messing with it for a few hours i fixed it; and here is how i did it. Solution: 1. Use GParted to resize an external HDD (enough to fit the win7 partition in unallocated space.) 2. Copy the Windows 7 partition (in GParted) off the computer onto the unallocated space on the external HDD. 3. Reformat the computers HDD to NTFS. 4. Copy back the win7 partition back to the beginning of the computers HDD. (I personally left “round to cylinders” checked.) 5. Once its done, exit GParted, unplug external HDD, and pop in the win7 install disk. 6. Boot from the disk, select language, etc. then click next. 7. Select “repair your computer”. 8. Before; my OS wouldn’t show up here, but since I did the previous steps it will find the OS. It will scan and I believe that it will tell you to restart because it fixed the OS. 9. Restart if it tells you to, and start back at step 6. 10. In essence, you need to go to “repair my computer” twice to do the same thing both times which is select your OS and click next. From there click “startup repair” and that should be it. 11. Enjoy windows 7 again.