operating system not found after updates

[joshalo]

Hi, My computer is a Lenovo x120e AMD 64. I have been running Ubuntu 12.04 LTS since April with no significant problems. Today, I installed recommended security updates which is something I do regularly. The system required restart to complete the updates and so I restarted the computer. Upon restart, I now get the error message "Operating System not found". I switched the bios to diagnostic mode and I see where the computer is finding my hard drive, "Fixed Disk: WDC etc." Prior to this problem, my hard disk was operating normally with no loud noises or other indications of a problem.

Unfortunately, I no longer have a good usb start up disk and this computer does not have a CD drive. I do have another computer running 12.04 but I have not installed the most recent updates on that one and it works fine. I do not, however, have a fast enough internet connection to download another copy of the operating system.

Am I the only one having this problem? What should I do next?

[pqwoerituytrueiwoq]

make sure the bios is set to boot the hdd, remove any sd card/usb drive and see if it boots
you can also use the boot menu and select your hdd there

[joshalo]

Thanks for the quick response. I have tried each of your suggestions and have the boot order set to hdd first. There are no periphery devices attached to the computer. Same error "Operating System not found".

I opened the back of the computer, removed the hard drive and replaced it, no change. I have an enclosure for a SATA drive so to check to make sure that the disk was good, I put it in the enclosure and mounted it on my other computer. My files are all visible. I ran disk utility and the disk is good with no bad sectors.

Unless the Lenovo's controller is bad, I believe the problem must be related to the security updates that I just installed. Is there a way to go back to the previous state of the drive before the updates? Can I do this with the disk as an external drive mounted on my working machine?

Josh

[joshalo]

So I was able to get a bootable usb start up disk and have used it to boot the Lenovo. The WDC hard drive is visible in the file system menu. I used disk utility to check the disk and adapter and everything is good.

[darkod]

Boot into live mode with the stick if you can, open Gparted and check whether you have the boot flag on any partition on the hdd. Some systems don't boot without any boot flag even though linux doesn't need it to work (unlike windows).

If there is no boot flag, set it on one of the partitions. If you have windows, set it on the partition where windows is.
If you have only ubuntu, set it to any partition, for example the root partition, but not to an extedned one. It has to be either primary or logical.

You set the flag by right-clicking a partition in Gparted and selecting Manage Flags.

See if that helps.

[joshalo]

Thanks for the suggestion,

I booted in using a live cd on a usb stick. I opened GParted and saw the HDD. A boot flag was set for sda1 with is a FAT32 100mb partition. There were no flags on the ext partition or the swap partition. Still, when I try and boot normally, it finds the HDD, beeps and goes to a screen that reads "Operating System not found". Is there a way to replace the boot partition with a new version without wiping the entire disk? What else can I try?

Josh

[Gamanet]

Hi!

I have the same problem after updating my 12.04...

It´s definatly not the disk causing the problems...

I guess the update did some changes to drivers needed for working with motherboard/chipset, etc...

Haven´t found a solution till now...

P.S: i´m also running a Lenove x121e, when i start ubuntu from cd/usb it works fine and i can access the disk... only booting from disk doesn´t work anymore... and yes, there is a boot-flag on the correct partition...

[darkod]

The thing that is confusing me is that Operating system not found is usually reported by bios, not by the bootloader or the OS itself.

If this is a bios message, what ever OS you have has nothing to do with it.

And the grub2 error messages are different, I haven't heard of this message to be part of grub2 messages.

[Gamanet]

Maybe that could lead to the right direction?

http://askubuntu.com/questions/13939...et-to-defaults

I´ve to install ubuntu on my netbook again to test by myself...


And you´re right - "Operating System not found" isn´t a grub-message..

[joshalo]

I'm glad to hear that I'm not the only one with this problem. I followed the links suggested and followed the instructions to reload grub using the usb live disk. This seemed to have worked as far as I could tell. However, no luck. Still get the message "Operating System not found" when booting from the HDD.