Installation ends succesfully, computer restarts and... Windows boots up.
My computer: old laptop HP Compaq 6710b (no UEFI, no secure boot).
Two hard drives:
- 1st is 240 GB SSD and 2nd is some old 200 GB HDD.
- 2nd drive is installed in special adapter which fits in optical drive bay.
2 Answers
Your problem is probably that, during installation, it / you picked the wrong option in "device for bootloader installation". (See here for a screenshot)
Your laptop presents the hard drive as /dev/sda, and the internal SSD as /dev/sdb (From the screenshot). Thus, the installer installed the bootloader onto /dev/sda by default (Assuming you didn't tell it to do otherwise).
The problem is that the laptop isn't looking on the HDD for the bootloader - it's looking on the SSD, and thus only sees the Windows 7 bootloader (Which is on the SSD, and not the Ubuntu one (grub), which is on the HDD.
See How can I repair grub? (How to get Ubuntu back after installing Windows?) for details on how to fix this, making sure you intall to /dev/sdb, or you can use Boot-Repair for this.
Another, possibly easier, option is to set the boot order in the BIOS set-up, so that it is set to boot from the hard drive.
Let me know if it helps.
- 4,047
I finally managed to regain access to my Ubuntu with following set of commands:
sudo mount /dev/sdb8 /mnt
sudo mount --bind /dev /mnt/dev/ &&
sudo mount --bind /dev/pts /mnt/dev/pts &&
sudo mount --bind /proc /mnt/proc &&
sudo mount --bind /sys /mnt/sys
sudo chroot /mnt
grub-install /dev/sdb
grub-install --recheck /dev/sdb
update-grub
exit &&
sudo umount /mnt/sys &&
sudo umount /mnt/proc &&
sudo umount /mnt/dev/pts &&
(All commands executed using Ubuntu 16.04 launched from USB drive.)

