[SOLVED] Startup problem

Since upgrading from 12.04 to 14.04 I have been having startup problems. Today there is a message:

Gave up waiting for root device. Common problems:
- Boot args (cat /proc/cmdline)
- Check rootdelay+ (did the system wait long enough?)
- Check root= (did the system wait for the right device?)
-Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/disk/by-uuid/5c14d0a9-6d0e-424c-a2db-da3ddd5539cc does not exist
Dropping to a shell!

BusyBox v1.21.1 (Ubuntu 1.1.21.0-ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands

(initramfs)

The motherboard is an Asus M5 A78L-M USB3

This machine acts as a file server, but fortunately there are backups on this machine.

Thank you.

Malcolm

ALERT! /dev/disk/by-uuid/5c14d0a9-6d0e-424c-a2db-da3ddd5539cc does not exist

The message above indicates that it can't find the root partition with the above uuid. Run the blkid command from a terminal from a Live CD and compare it to what you have in the grub.cfg file.

Ultimately I'd probably try re-installing grub. First you may want to boot from a CD/DVD/USBThumbstick and see if you can mount your system's hard drive, check it out to see if the files are visible, and intact. Check the /boot directory. If you see files, all appears normal, you could maybe also run a fsck on that disk and see if there are any errors detected. Depending on the outcome I'd take my next step. The grub thought was that your disk is OK and just that grub does not properly understand where your system is.

Before trying any changes, if you are able to view your files via a boot from a Live distro, save backups of your data.

Thank you both for your replies, I shall work through your suggestions.

There are two things I forgot to mention which may have a bearing on things. There are two 1TB hard drives fitted and twice the machine has forgotten which drive it is supposed to be booting from also sometimes the multi-core does not start properly so I am beginning to wonder if it may be a hardware problem.

I am sorry to have missed these points before but I was so pleased to have copied the error message from one machine to another that it slipped my aged mind.

Thank you.

Malcolm