Removed ubuntu 14, put 15 hornbeam no, what to do?

Question

GRUB

Before that, I demolished the 14th version of Ubuntu, because the touchpad did not plow. And after that, when loading such a command line grub> and in it it was necessary to write Exit to start Windows. Now I put a tag, but the hornbeam did not appear. Did it like this:

sudo mount /dev/sdxN /mnt
sudo grub-install --root-directory=/mnt /dev/sdx
sudo update-grub --output=/mnt/boot/grub/grub.cfg
sudo reboot

not a fig. There's some kind of error already forgot what. Something about the partition and bios. Need help

Answer 1

There was some kind of answer already forgot which one. Something about the partition and bios. Here is your help.
But seriously, then most likely you have a UEFI / GPT boot mode, in which case GRUB is installed in ESP, and if it is not there and / or there is a desire to boot in legacy mode from a disk marked in GPT, then you need to create a small partition in any its place with the legacy_boot flag. Then reinstall and reconfigure GRUB 2.
Answer as usual in ArchWiki
https://wiki.archlinux.org/index.php/GRUB#GUID_Par...