Linux, Windows 7 boot removed

Question

I was using linux for a while. Few days ago I made a fresh install of Windows 8 I deleted everything on disk (on purpose). Now I wanted to have dual boot with arch linux. So I installed linux, I created three new partitions and left 2 windows partitions alone:

2GB swap
12GB root
12GB home

After installation I was asked to install grub boot loader (I'm not sure if this is correct), and as I did long time ago I just pressed "yes", "yes"... Installed it on /dev/sda which I guess was used to boot windows before.

Now I have only two choices when I am booting my machine: Arch and Arch fallback.

I did same thing about year ago but the difference was I had three boot choices: Windows, Arch and Arch fallback. What Am I missing here how to

Answer 1

If the Windows partition is still there, then you probably just need to add the entry for it in Grub. sudo update-grub2 should work (if it doesn't run, you might have a different version of Grub. Try sudo update-grub). If not, try adding the entry manually. http://ubuntuguide.net/manually-addingremoving-entries-to-grub-2-menu has a good tutorial on how to do this.

Answer 2

It sounds like you formatted over Windows. /dev/sda is the hard drive as a whole. /dev/sda1 would be a partition on the hard drive. You specifically mentioned /dev/sda so I'm guessing it did a format and repartition of the entire drive.

Ideally, you should have used something like gparted to resize the Windows partition, allowing room for Linux, THEN installed Linux to the new, empty partition while leaving the Windows partition alone.