# Ubuntu – 0xc000000f error when starting Windows from Grub

Recently I corrected the dual boot by re-installing the grub bootloader.

I did that by first adding an entry pointing to Linux in easyBCD settings.
Then, when I restarted the computer it showed Windows 7 and Grub Bootloader in Windows' bootloader. When I selected the Grub bootloader, it took me to Ubuntu Grub 2 bootloader from where I booted Ubuntu. Then I installed Boot-Repair and did receommended repair.

Everything went fine, on startup grub bootloader appeared, but when I select Windows 7, it would then take me to the Windows bootloader with choices of Windows 7 and Grub bootloader, which I inserted using easyBCD.

I removed this entry using easyBCD again and restarted. And since then, my Ubuntu is working fine but when booting Windows, it gives an 0xc000000f error.

I have generated a report using boot-repair.

What do I do next?

So you are using GRUB, selecting the windows 7 entry, selecting Windows in the windows boot manager, and then it fails with the error.

This guide should work, however I have not tested this myself and I am not responsible for any data loss. If you are paranoid I would make a entire clone of your hard drive to somewhere else.

Things you will need

• USB with the Ubuntu live desktop (aka Ubuntu installer)
• Windows 7 repair/install media

What to do:

1. Boot into the Windows 7 repair/install media, and at the language screen, then press SHIFT + F10 to get a command prompt. Type bootrec /fixmbr followed by bootrec /fixboot.
2. Reboot your PC to the hard drive. Windows should boot, without any sign of the boot manager.
3. Reboot into the Ubuntu live desktop media and install boot repair, and have boot repair install GRUB (or use the command line if you know the grub-install params).
4. Reboot to your hard drive, and you should see the GRUB menu with Ubuntu boot options and a Windows boot option. Boot into Ubuntu, and confirm it boots.
5. Boot into Windows, install EasyBCD (if it isn't already installed), and add the Linux option to the Windows boot manager.
6. Reboot your PC, select the Windows option in GRUB. You should see two options for booting at this point - one for Windows and one for Linux/GRUB that you added earlier. Select the Linux option, and if it goes back into GRUB, then the tutorial is complete and your boot system should work again!