Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

SO, I have been trying to get ubuntu linux on my windows 8 pre-installed VAIO laptop. The USB stick containing the ubuntu boot wasn't working right, so I went into the BIOS and changed UEFI boot to legacy. Now when I turn on my computer with the USB, it displays, "SYSLINUX 4.04 EDD 2011-04-18 COPYRIGHT (C) 1994-2011 H. PETER ANVIL et al". Without the USB, it just says that there is no operating system, and Windows 8 doesn't boot. I am worried that I broke my computer. Can anyone tell me how to change back to UEFI so that Windows 8 will boot, or even how to get the Linux Ubuntu USB to boot right? Thanks. 1 second ago - 4 days left to answer.

share|improve this question

Take the hard drive out of your laptop. This should allow you to get into the UEFI. If that does not work, the instructions (take from the VAIO User Guide) to get into the UEFI are as follows:

  1. Press the ASSIST button while your VAIO computer is off. The VAIO Care Rescue Mode screen appears.
  2. Select Start BIOS setup. Enter a password if it has already been set. The BIOS setup screen appears.

Now, you should be able to change back to UEFI from Legacy boot. As far as the second part of your question, this should help you in doing what you need to do. To make this answer more complete, I will add that guide here:

If you want Ubuntu on the same disk as Windows 8.1, here are the steps to go through:

1) Turn off Windows Fast Boot

2) You need to shrink the main Windows 8.1 partition. This can be tricky, as Windows expects a certain partition scheme to be used. Let me show you a diagram:

[(Windows RE Tools)(EFI System Partition)(Microsoft Reserved Partition)(Windows 8.1)(Anything else)]

You can use your favorite tool to edit these partitions. I prefer Gparted, but any good disk partitioning tool can handle this. Backup your Windows install first. Then, resize the Windows 8.1 partition so that you have enough space for another OS. I prefer to give my Linux installs about 50-100 GB of space (for expandability).

3) Download your Ubuntu (use 64 bit only and I suggest 13.10) iso and put it on some media (CD/DVD/USB/(insert your preferred media here)) by using your favorite tool (most people prefer Rufus) or dd.

4) Shut off Secure Boot and Fast Boot in the UEFI. DO NOT TURN ON LEGACY BOOTING (if your motherboard supports UEFI only booting without Secure Boot and Fast Boot on.)

5) Insert your install media and install Ubuntu in the partition you made earlier. Make sure that for your EFI boot partition, you make the installer use the EFI System Partition already created by Windows 8.1. The partition should be something like sdXn (replace X with the drive it is on and n with the partition number, such as /dev/sda2), but this could be different. DO NOT REFORMAT THIS PARTITION!! You are only going to tell the installer to use it as the EFI partition. It will put the grubx64.efi bootloader for Ubuntu in this location.

6) With that done, continue the install as normal and set up your partitions as you see fit. Once the install is finished, you should be able to boot into Jessie easily.

If you are trying to fix an existing install of Ubuntu, you will need to do:

sudo apt-get install grub-efi-amd64

sudo modprobe efivars

sudo grub-install /dev/sdx (x being the drive Ubuntu is installed on)

sudo update-grub

From there, the UEFI should use Grub-EFI as the bootloader. I have not found a way to get the Windows 8 bootloader to see and allow Linux to boot in UEFI. YYMV.

share|improve this answer

You can change Legacy back to UEFI in Bios (as you changed UEFI to Legacy).

Btw, did you tried to wait, when

SYSLINUX 4.04 EDD 2011-04-18 COPYRIGHT (C) 1994-2011 H. PETER ANVIL et al


share|improve this answer
I cannot access BIOS without already being in Windows 8. I tried waiting for a few minutes and nothing happened. – user132734 Feb 16 '13 at 23:10
Can you try to boot another Linux distro or create bootable usb with different sofwtare? – zatloukal-frantisek Feb 16 '13 at 23:15
Probably. Do you recommend any? – user132734 Feb 16 '13 at 23:21

Go back into your firmware (what you called "BIOS") settings and change back whatever you altered. Assuming you didn't delete your Windows boot loader, that should get the computer booting to Windows again. If it doesn't, you need to be more precise about what you've done; I'm afraid your description isn't very clear. For instance, did you actually do an Ubuntu installation, or does the installer hang after displaying the SYSLINUX message?

share|improve this answer
I am not sure exactly how to re-enter firmware settings because I've only ever been able to do it from inside Windows 8. Nothing comes up after the SYSLINUX message, which makes me think that there is a problem with the ubuntu boot on the USB – user132734 Feb 16 '13 at 23:14
Contact your manufacturer's tech support line to learn how to get into the firmware settings. Some of them are starting to tie it to Windows, which is BAD DESIGN. If you've got such a system, they might know of an obscure way around it; or you may be able to do something with a bootable CD or USB flash drive; or you may have to return the computer for repair/exchange/refund. If a return is necessary, try to get a refund and buy something else. – Rod Smith Feb 17 '13 at 0:10

Do you have (ASSIST) button on your laptop left of power key..if you do when computer off keep assist press till you see bios hope this helps

share|improve this answer

Windows 7 on UEFI requires that the disk partitions use GUID partition table (GPT) rather than the traditional MBR partitioning format found on BIOS systems. Unfortunately, windows provides no way of converting an MBR partition to a GPT one non-destructively. However, if you don't mind copying data off your drive, converting, then copying it back then you could use windows to do it as described here.

If you don't want to backup the data first and have access to a a linux machine that you can install the drive in, there are tools in linux that will allow you to convert the partition type non-destructively as described here. If you don't have a linux box handy, you can also try creating a linux boot CD and booting from that. Searhing for "convert MBR to GPT" brings up other tools, but I have never tried them

share|improve this answer

Just hold the Assist button and keep pressing F2.

share|improve this answer
Your answer would be improved if you added more information to it. There is more information about using the Assist button in this chapter of the VAIO User Guide. Also you should add information about what happens next after pressing Assist + F2. – karel Jul 13 '13 at 4:21

Though it may be different for each computer manufacturer, MY Toshiba bios can be accessed using the following method:

With computer COMPLETELY powered off, press the power button, then immediately begin pressing the F12 key, over and over until your Boot Menu appears, offering which device you want to boot from. From there it should have an option to open Setup, which will be your bios settings.

share|improve this answer
This question is not about the BIOS but UEFI. – Braiam Sep 20 '13 at 3:05

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.