"Unable to install GRUB in /dev/sda" when installing GRUB

I recently bought a shiny new Lenovo Yoga 2 Pro and I want to dual boot it with Ubuntu for studying purposes. Its built-in OS is Windows 8.1 and it has a 256GB SSD.

I've made a separate 90GB partition just for Ubuntu and a live USB to install it.

The first time everything seemed to work great, I solved the wifi issued by blacklisting ideapad_laptop, the installation went flawlessly and Ubuntu worked fine.

When I got up the next morning and turned on my laptop it booted into Windows right away without ever showing the GRUB menu. So I tried to reset, and checked my partitions with the Disk Manager and everything looked fine. Since I couldn't find a solution online I went ahead and formatted the partition to try and install again. This time and every time since, the installation was aborted and I got a fatal error saying:

Unable to install GRUB in /dev/sda
Executing `grub-install /dev/sda` failed.
This is a fatal error.

Can anyone please suggest a solution to this problem? If any further information is needed I would be happy to provide it. Thanks.

When installing I get the following in details:

ubuntu kernel: [ 1946.372741] FAT-fs (sda2): error, fat_get_cluster: invalid cluster chain (i_pos 0).
ubuntu grub-installer: error: Running 'grub-install --force failed.

I just had this problem installing Ubuntu 14.04 from a USB stick to a hard drive.

The problem was the USB stick was /dev/sda, installing to the hard drive /dev/sdb

Even though the installer knew to install to /dev/sdb, it then tried to install grub to the MBR on /dev/sda, and failed. The workaround was to go back to the menu, try again, say NO to automatically install to MBR of first hard drive and manually tell it /dev/sdb.

Then everything worked.

I finally got it working, not sure which of the following did the trick but I:

1. Disabled Lenovo Fast Boot in BIOS.
2. Disabled Secure Boot in BIOS.
3. Booted from Live USB.
4. In boot menu Added backlight=vendor in Try Ubuntu configuration text just before quiet splash.
5. Chose Try Ubuntu.
6. In terminal ran sudo rmmod ideapad_laptop to enable wifi.
7. Ran installation and chose to install updates during installation.
8. EFI partition was selected automatically so I assigned 9700MB for swap space and 80GB for Ubuntu.
9. After installation completed added backlight=vendor to /etc/default/grub before quiet splash and then ran sudo update-grub.
10. Blacklisted ideapad_laptop to enable wifi.
11. Works fine so far. Thanks to everyone for the help!

I got the same error while installing Ubuntu 20.04. Turned out that I had created "logical" instead of "primary" partitions during the installation process for both my EFI and root partition. I ran the installation again, this time configuring both partitions as a "primary" partition, and the error was gone this time.

I had a similar problem. What I did was to leave the installation as it was, then I made sure my drive was in UEFI mode and booted from a live CD and installed boot-repair.

To do this I had to add the yannubuntu repository and then download it with apt-get. This was done the following way:

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

Then, when the program was launched, I checked all the options in Advanced Options > Main Options and clicked Apply.