After reinstalling Linux Mint, Windows 7 does not boot

I had a dualboot setup in my computer: On one side, Linux Mint ( /dev/sda2 ), on the other, Windows 7 ( /dev/sda3 ). I ran into some weird problems with Mint, so I decided to install the last version and give it a try.

The thing is that, after install the new Linux Mint, Windows 7 don't boot. I got to the Grub screen, select Windows 7, accept and then grub appears again. Linux mint boots normally.

• I downloaded rescatux and tried to restore grub (I battled time ago with similar problems). Nothing.


• Also tried the MBR restore for windows. Nothing.


• Boot-repair did nothing.


• I installed grub customizer and put Windows 7 the first on the list and nothing.

So... I'm pretty much clueless. Most of the questions are the other way around (Installing Windows "hides" grub, then Linux Mint does not start), so it seems if someone has had the same problem that me, is very well hidden in the internet. Any idea?

Edited, this is the script for Windows:

insmod part_msdos
insmod ntfs
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 --hint='hd0,msdos3'  264CA3CF4CA39857
else
  search --no-floppy --fs-uuid --set=root 264CA3CF4CA39857
fi
parttool ${root} hidden-
chainloader +1