Laptop: acer, Aspire V 13 V3-372-57M8
Notes:
- I'm able to load ubuntu from flash disk (which is how I am writing this post)
- holding shift after reboot wont bring up the grub menu
- Using boot repair didnt help, here is the log.
Note the "No boot loader is installed in the MBR of /dev/sda."
In some online resources I read it is not an issue with new systems. - adding "boot" flag to /dev/sda2 didn't work (file system ext4, see screenshot)
- I'm trying to boot in UEFI mode
I tried for a couple of hours to get this to work, no luck so far ...
I'm on an Acer Aspire and I've been facing similar issues. Tried boot-repair, manually updating and reinstalling grub, turning secure boot off with no success.
You have to select the grubx64 uefi file as trusted from BIOS. Detailed instructions can be found here - https://askubuntu.com/a/630662/237187