I created a new partition on Windows from unallocated space (I already had 4 primary partitions, so it seems it created a dynamic partition), then when I reboot I enter in the GRUB Rescue.

I used instmod and then I could boot to Ubuntu.

I tried to install GRUB with boot-repair and from command line

Using boot repair

First I get the error

SFS detected. You may want to retry after converting Windows dynamic partitioning (SFS partitions) to a basic disk

Then I just continued with boot repair and

GRUB failed to install to the following devices:


Command line

sudo update-grub
sudo grub-install dev/sda

I get the same GRUB failed to install as I mentioned above

Using bootable usb

I tried boot repair and I get the same errors as when using it on PC.

Windows is not booting, when trying I get:

error: device format "lad/a1eb ... /volume1" invalid must be (f|h)dN with 0<=N<128

My HD:

enter image description here

  • SFS is Windows proprietary dynamic partitioning which does not work with Linux. Do not create partitions with Windows if you have used all 4 primary partitions. Best to just undo, but Microsoft makes it easy to create dynamic but has no undo. Some third party tools may work, but good backups required. askubuntu.com/questions/482768/… and:ubuntuforums.org/… There is a new ldmtool that may let you see partitions. – oldfred Nov 20 '16 at 19:36
  • Just to add, before it everything: Windows and 2 Ubuntus were working fine. After I allocated one partition, everything started. – Vitor Abella Nov 20 '16 at 19:39
  • Mistake was adding partition using Windows, not gparted. But if you had made a new logical it would have been ok. Windows tools for Windows & Linux tools for Linux. – oldfred Nov 20 '16 at 19:47
  • @oldfred I couldn't add a partition with gparted because it said I already had 4, then I tried with windows... and my objective was to use this partition with windows, not ubuntu. – Vitor Abella Nov 20 '16 at 19:49
  • @oldfred do you think if I unallocate all sda4 (see figure) it will boot normally? I have backup and I think it is easier to unallocate and install windows than undoing dynamic disk. – Vitor Abella Nov 20 '16 at 19:55

What I did: I formated the disk and installed everything again. As I had backup of windows partition, it was just time loss.

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