I also occurred same problem but I can solve it using following link
http://blog.wittchen.biz.pl/ubuntu-system-boot-problem/
Attempt #1
First, I tried to change rootdelay as error message said. I opened file /etc/default/grub
I found there the following line:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
and changed it to:
GRUB_CMDLINE_LINUX_DEFAULT="rootdelay=90 quiet splash"
rootdelay became longer, but unfortunately it didn’t fix the problem in my case.
Attempt #2
I edited /etc/fstab file. I executed the following command in terminal: sudo gedit /etc/fstab and edited fstab file in gedit. In the beginning my file looked like that:
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda1 during installation
UUID=96889309-5f73-4688-8354-e64cd1bb158f / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=480cc3f7-a39d-4d0f-93d5-49fc8df1a392 none swap sw 0 0
Then, I commented one line and added another one describing /dev/sda1 disk device. Now, my file looks as follows:
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda1 during installation
UUID=/dev/sda1 / ext4 errors=remount-ro 0 1
# UUID=96889309-5f73-4688-8354-e64cd1bb158f / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=480cc3f7-a39d-4d0f-93d5-49fc8df1a392 none swap sw 0 0
Problem still existed, so I tried another attempt to solve it.
Attempt #3
I opened terminal and typed the following command:
sudo grub-install /dev/sda
and then I typed another command to update grub:
sudo update-grub
After all of this, I rebooted computer and finally, error disappeared and problem was fixed!
linux-image-extra
, or it got "destroyed" when upgrading kernel)