Comment 2 for bug 1547471

From the log:

    update-initramfs: deferring update (hook will be called later)
    cp: cannot stat ‘/boot/initrd.img-4.4.0-6-generic’: No such file or directory
    Failed to copy /boot/initrd.img-4.4.0-6-generic to /initrd.img at /var/lib/dpkg/info/linux-image-4.4.0-6-generic.postinst line 745.
    dpkg: error processing package linux-image-4.4.0-6-generic (--configure):
     subprocess installed post-installation script returned error exit status 2

The OR reports that he has a real file as /initrd.img, a zero length file.