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So, I have a decently standard Windows7/Ubuntu dual-boot setup, and (since Ubuntu is my usual operating system) I found I needed to grow my Ubuntu partition and shrink my W7 partition. Originally, my system (500G) looked like this:

  • W7 Boot Partition (1.5G)
  • Ubuntu (around 240G)
  • W7 (same as Ubuntu) (on an extended partition, all by itself)
  • Swap (rest of disk, around 16G)

Now I'm no stranger to partitioning and filesystem tools, especially GParted, which I used on a Linux boot disk. After my partition editing, the partitions are laid out the same, except the Ubuntu partition is now 407G and the W7 partition is smaller to compensate. I had supposed, based on, that I would be able to run the W7 install disk in recovery mode and have it deal with the rearrangement, then possibly reinstall GRUB or something.

Well, now the W7 install disk doesn't even see my W7 installation. All my files are there, the NTFS is perfectly clean, no problems there, but the install disk won't notice it. (Of course, the GRUB entry works fine but the W7 boot partition (which I didn't change) refuses to boot it.)

So, basically, any ideas on how to fix this? I don't especially want to rerun the entire install procedure because I'll have a bunch of programs to reinstall (never mind redoing GRUB), but I fear that might be the only option.


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Looked up and tried anything with BCDEdit? EDIT: – francisswest Sep 26 '12 at 21:41
Interesting, I'll give it a shot... – Actorclavilis Sep 26 '12 at 21:42

When you resize or move partitions it happens that Windows BCD (boot config data) no longer reflects new partition layout and boot fails.

To repair Windows BCD and Windows booting you can either run StartUp Repair (up to three consecutive times with rebooting after each run) or use following commands on recovery console:

  1. bootsect /nt60 all /mbr
  2. bcdboot c:\windows - assuming Windows is on c: (change drive letter if necessary)

After Windows can boot from hdd you can reinstall GRUB from Live CD which will recreate the dual-boot under control of GRUB (GRUB installed to MBR).

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