• Using the simple Windows GUI and instructions you can install Grub2Win quickly and safely. Boot-time messages and help can be displayed in multiple languages. Once installed the interface makes it simple to boot into whatever operating system you want with ease. Included are samples for Remix, Android, Ubuntu, Debian, Suse, Fedora, Mint,.
• Ubuntu and many other Linux distributions use the GRUB2 boot loader. If GRUB2 breaks—for example, if you install Windows after installing Ubuntu, or overwrite your MBR—you won’t be able to boot into Ubuntu.

• Install Grub2 From Windows
• Install Grub2 On Windows Partition
• Grub Windows 7

Grub2Win is a tool that lets you boot grub2 from your PC's EFI firmware or MBR. It supports Windows 10, Windows 8, Windows 7, Vista and XP. Download this simple Windows program and instructions that help you get grub2 booting quickly. All the files for Grub2Win reside on the Windows C: drive.

Possible Duplicate:
How can I repair GRUB? (How to get Ubuntu back after installing Windows?)

I installed Windows 7 after it crashed, and now I am unable to boot Ubuntu. Ubuntu partitions are still there. I tried using Boot-Repair, but it didn't work!

marked as duplicate by Eliah Kagan, Jorge Castro, fabricator4, stephenmyall, hhlpJan 11 '13 at 10:50

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

6 Answers

You can re-install grub in the Master Boot Record using the LiveCD for you distribution version,

It goes like this:

• Boot from LiveCD ⋯ please try to use a LiveCD that has the same version of Grub2 as the installed version

• Mount the root of the installed Ubuntu at /mnt

• Change root

• Update grub

• Install grub

• Reboot

The above steps are from near the bottom of the Ubuntu Community Documentation of Grub2

After booting from the liveCD ( select 'Try Ubuntu' on the opening screen)

Then start up a terminal (dash, type-in terminal, … )…

• It may be easier to open this web page while running LiveCD. Firefox should allow you to do this.

Type in the terminal sudo fdisk -l - and enter your password if asked. That's a lower case L. Find the installed Ubuntu partitions, (from mine with other disks snipped ― here):

Find your Linux installation (Id=83, System=Linux0 then type in

but use your partition instead of /dev/sde3(my root partition is sde3, sde7 is my home partition).

This is assuming that you do not have a separate /boot partition. If you do, you will need to also mount it by typing

where sd·· is the partition where you installed the separate boot directory.

ls /mnt - just checking to see if I got it right:

You should test to see if the boot directory is properly installed. Type in ls /mnt/boot and if it is empty, the boot directory is not installed. It should look something like this:

Then:

Example:

Now to re-install grub in the MBR. You will need to know which disk your system boots from, and find it in the fdisk -l listing you have already done. Then type in sudo grub-install /dev/sd replacing sd· with the disk you will boot from.

Then type in Crtl-D to exit chroot.

Then type in sudo for i in /sys /proc /dev/pts /dev; do sudo umount /mnt$i; done - as one line

If you mounted a separate /boot partition, type in sudo umount /mnt/boot

Then type in sudo umount /mnt

Then type in sudo reboot to restart he system (remember to remove the LiveCD).

Hopefully, grub will be installed.

keepitsimpleengineerkeepitsimpleengineer

Try this..

To recover grub:

1. Open the live version.
2. Open the terminal and run sudo fdisk -l to see where Linux is installed.
3. Run sudo mount /dev/sdaX /mnt where x is the number you have found Linux word in
4. Run sudo grub-install --root-directory=/mnt /dev/sda to install grub.
5. Run sudo update-grub to update grub and if this command didn't work run it after rebooting.
6. Reboot.

Kevin BowenBlack BlockBlack Block

Boot-Repair is a simple tool to repair frequent boot issues you may encounter in Ubuntu like when you can't boot Ubuntu after installing Windows or another Linux distribution, or when you can't boot Windows after installing Ubuntu, or when GRUB is not displayed anymore, some upgrade breaks GRUB, etc.

Remark: this can also be performed from a live-CD or live-USB.

Either add ‘ppa:yannubuntu/boot-repair’ to your Software Sources via the Software Centre or, for speeds-sake, add it using a new Terminal session:

Boot-Repair can be installed & used from any Ubuntu session (normal session, or live-CD, or live-USB). PPA packages are available for Ubuntu 10.04, 10.10, 11.04, 11.10, 12.04 and 12.10. source

RingtailRingtail

After installing Windows 7, Windows bootloader has overridden the MBR.

To fix this you can install a program 'EasyBCD' in Windows

Follow these steps to restore GRUB when after installing EasyBCD:

1. Launch the program and select ADD NEW ENTRY from the EasyBCD Toolbox

2. Select the 'Linux/BSD' from the operating systems column

3. Choose GRUB (Legacy) under type and Click on the ADD ENTRY icon

4. Choose YES to the restart prompt

5. GRUB will be displayed after the restart which will detect the Ubuntu partition for you to be able to boot into Ubuntu

GOOD LUCK

Download link: http://neosmart.net/download.php?id=1

Jorge CastroMysterioMysterio

Boot-Repair works:

• I had Windows XP and Ubuntu on my PC.
• I installed Windows 7 which resulted in new boot loader without Ubuntu.
• I installed Boot-Repair with the startup disc and GRUB was updated along with Windows 7 and Windows XP.

Peter Mortensen

One nuance to be careful about - the instructions say to check if you have a separate boot partition, and if so then do sudo mount /dev/sd·· /mnt/boot. I got confused here - I did have a boot partition that was not my Linux, it was my base partition (/sda0). So I did that command, and ended up getting a grub menu that only showed my Windows boot. I re-ran the procedure without the doing the sudo mount /dev/sd·· /mnt/boot and it worked beautifully - my old GRUB menu was back, with all the Linux options as well as Windows. The instructions are only referring to a separate Linux boot partition, not for the case where your boot partition is not Linux.

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Install Grub2 From Windows

I have Windows 10 dual boot with CentOS. However, I can't access CentOS, my machine start automatically with Windows, and there is no Grub screen to choose CentOS. Can you guys help me? Thanks.

1 Answer

I made a Tutorial on the installation of Grub on CentOS 7:

Installation of Grub2 and dual boot with windows 10

If your Grub configuration is not as you like follow this tutorial.First reinstall Grub.

Login as root in a terminal

Install Grub2 On Windows Partition

In another terminal , get information about your Windows 10 hard drive, in my case it was named '/dev/sdb1'

In my configuration, my windows 10 disk was on another hard drive. Follow only if you are in the same situation.

Grub Windows 7

In the root terminal, navigate to the grub configuration directory

Now we must find the UUID of your Windows 10 hard drive, enter this command in your non-root terminal

Find the UUID code next to your disk something like: 40S863A9D8619F12

Now in the root terminal enter the command:

Inside this file enter your windows 10 configuration using GRUB standard. Use the UUID code previously found inside the configuration. In my case my config is:

Airbus A350-900 XWB with 39 repaints, on this new model (FSPainter) animations that did not work in the previous version now work (ailerons, reverses, rudder etc). Since there is no 3D freeware virtual cockpit for the A350, the cockpit of Thomas Ruth's A330NG has been put in place and adapted to the A350. Fsx a350 freeware.

Save and exit nano. Now we need to generate a new GRUB configuration file. Enter the command:

Voilà !!!! Try the configuration with a fresh restart

Source:http://dareneiri.github.io/Configuring-Grub-2-on-CentOS-7/https://ihaveabackup.net/article/grub2-entry-for-windows-10-uefi

(Optional) Install GRUB customizer

If you want to have a sexy GRUB menu you can install grub-customizer using this tutorial:https://centos.pkgs.org/7/epel-x86_64/grub-customizer-5.0.6-1.el7.x86_64.rpm.html

you can find more tutorial at: https://github.com/Winterhart/CentOS7-Setup/

Rui F Ribeiro

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