Ubuntu 14.04 and Windows 8.1 dual boot, boot menu not appearing after windows "refresh". Looking for help in getting dual boot capability back

Question

I can't get a boot menu to appear. Can anyone help me to restore it, or tell me how to be able to choose which OS to boot into at startup?

I ran Windows 8.1 and Ubuntu together no problem for the better part of a year.

I have an Acer Aspire ES1-512-C1W0 running windows 8.1 and Ubuntu 14.04 trusty. In a moment of craziness I ran Windows "Refresh" (no backup:(). That worked ok, but the boot menu that used to appear is gone. I can boot into the live USB no problem. I have read many posts and tried the following.

Disabled fast and safe boot.

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

(tried several times thinking I had it wrong the first time)

The boot repair link is http://paste.ubuntu.com/25762750/

[2

I don't know much about Linux, just learning, so I would appreciate if you could be specific with any advice.

Per the suggestion of duplicate

The first reference in that answer was suggested below and caused an error.

The second comment essentially does the same just further into the process.

Neither Easyuefi nor EasyBCD saw my Ubuntu partition. They are talking about selecting the Linux partition and moving it "up" in the boot order. I can't see that partition anywhere but on gparted, and so can't move it "up".

There is a long chain of comments and solutions here I haven't tried them all yet.

Message from EasyBCD

EasyBCD has detected that your machine is currently booting in EFI mode. Due to limitations set by Microsoft, many of EasyBCD's multi-booting features cannot be used in EFI mode and have been disabled. Linux doesn't show up and the tab it has the options greyed out.

I got it to dual boot again. The last action I took was listed in the answer below in the "Windows 8 removes Grub as default boot manager" Link

The key command seems to eventually have been:

bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi

After that I rebooted and presto the boot menu was back.

In the interim I tried a bunch of things listed on various pages, none of which seemed to do anything. I did try EasyUEFI again and was able to move the boot order of windows to the bottom. None of the partitions listed were names linux or similar, and there seemed to be no effect from this, for what it's worth.

I consider this closed from my end. I am not sure if I am supposed to take any action to indicate that other than checking the answer below which I did.

Answer 1

In theory, the following command, typed from an Ubuntu emergency disk booted in EFI mode, should fix the problem:

sudo efibootmgr -c -d /dev/sda -p 2 -l \\EFI\\ubuntu\\shimx64.efi -L ubuntu

That said, it looks like Boot Repair has tried this and failed. This puts you in a "messed up system" scenario. Most likely your NVRAM settings are corrupt and are confusing the EFI. Resetting everything to the default might help. If not, there are a number of other workarounds, which are described in various existing questions and answers here, such as:

• efibootmanager -o changes are lost on reboot
• Windows 8 removes Grub as default boot manager
• How can I repair grub? (How to get Ubuntu back after installing Windows?)

Answer 2

I was in a very similar position with my dual boot laptop on which the recent automatic Windows 10 update trashed my GRUB options and would only boot into Windows. It appeared that my Ubuntu 16.04, on which I have all my important work, had gone. I fixed it yesterday with boot-repair, when I thought all was lost and that I would have to reinstall Ubuntu and start from scratch. I only keep Windows because it was on it when I got it and I paid for it. All I ever do on Windows is scan for viruses, then go back to Ubuntu. So don't give up and reinstall Ubuntu, try boot-repair again.

This is what I did:

I booted with a live Ubuntu dvd, then installed boot-repair as you did. I then typed boot-repair and took the 'recommended' option. This gave me the grub options back on boot.

In case this happens again I followed the recommendation to build a boot-repair live USB. I did this on my Windows machine using Rufus to burn it. (Google for rufus + usb to find a site from which to download a burner for Windows) I also down loaded the 64 bit iso from Source forge boot-repair link and made the live usb. This makes it quicker to boot from the usb and it comes with a mini version of Linux and a GUI.

Give it another go before you trash your existing Ubuntu partition, you have nothing to lose.

Answer 3

After Windows update messed up dual-boot on a PC, I found the easiest fix was to reinstall Ubuntu.

1. Image the whole disk, ensuring that you have access to each partition (particularly the ext[n] one with Ubuntu). Windows utilities such as Macrium Reflect Free, as well as Linux dd and clonezilla do creditable jobs.

2. Using the Ubuntu Live media, install Ubuntu... you may need to mark the ext[n] and swap partitions as unused free space, first.

3. When satisfied that the new, minimal, installation dula-boots correctly with Windows, restore the ext[n] partition with your previous Ubuntu setup saved in step 1.

While this seems a bit drastic, I found it only took about 1/2 hour, far less time than it takes for a Windows installation.