After installing Ubuntu in a dual boot with Windows 7, I could not at first boot into either Ubuntu or Windows 7.
I then ran boot-repair from a live USB and restarted. After this, I was able to boot into Ubuntu 14.04. But Windows 7 still refuses to boot.
Grub shows the entry for booting Windows, but after selecting Windows, I am presented with the Windows screen, followed by a quick flash of a blue screen, then dumped back into grub.
Some additional info:
When I ran boot-repair, it mentioned that my NTFS was now SFS, and it had an LDM blocker.