It's odd that reinstalling grub didn't work. Your Windows distribution shows up on the Grub menu but you get errors when you select it. The only idea I have is to manually add another entry for your windows distribution to the grub menu. Having perused through the Grub 2 tutorial, I think it can be accomplished by doing the following:
Navigate to the /etc/grub.d/
directory and create a new file. The name of the new file should be something like 25_Windows_7
. The directory /etc/grub.d
contains scripts for adding new items to your grub menu. The order in which these scripts add items to the menu are determined by the number at the beginning of the name. In the file write:
#!/bin/sh -e
echo "Adding Windows 7 to GRUB 2 menu"
cat << EOF
menuentry "Windows 7" {
set root=(hd0,1)
chainloader (hd0,1)+1
}
EOF
replace the occurrences of (hd0,1)
with the partition of your windows distribution. I.E. if its sda4 then you would write (hd0,4)
.
Make the file executable by chmod +x 25_Windows_7
.
Now when you run update-grub
this new menu item should appear in Grub2's menu.
I have no idea if I even explained it right, but the Grub 2 tutorial can be found here.