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

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 had this issue when installing Ubuntu (not dual-boot) in my new build. None of the boot options described above would work for me.

I had to disconnect my SSD and all USB devices so that Ubuntu would only recognize the 1T HDD for installation.