Grub won't boot Windows 7, but EFI will

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Hi! I have Fedora 24 installed alongside Windows 7.

I am able to boot Fedora kernels just fine, but whenever I try to boot the Windows installation, nothing happens. The boot just gets stuck displaying a single underscore _ , and no other error messages.

When I go into the grub2 command prompt, and try

chainloader /EFI/Microsoft/Boot/bootmgfw.efi
boot

the same thing happens: the screen just freezes, becomes unresponsive and Windows doesn't boot.

The strange thing is: if I choose Windows from my Bios startup options, it boots perfectly fine.

System information:

• System: Lenovo ThinkPad x230
• Partition Type: gpt
• Boot Type: UEFI
• Secure Boot: OFF

Output of efibootmgr:

...
Boot0018* Windows Boot Manager
Boot0019* Windows Boot Manager
Boot001A* Fedora

Boot entry information for Windows:

$ efibootdump Boot0018
Boot0018: * Windows Boot Manager HD(2,GPT,a299fff2-ba84-4596-b79e-8e13940485e2,0x40800,0x32000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)

Boot entry information for Windows:

$ efibootdump Boot0019
Boot0019: * Windows Boot Manager HD(2,GPT,a299fff2-ba84-4596-b79e-8e13940485e2,0x40800,0x32000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}...a.................

As you see, I have two boot entries in the EFI boot manager, but they both work perfectly fine.

Entry for windows in /etc/grub2-efi.cfg:

### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'Windows Boot Manager (on /dev/sda2)' --class windows --class os $menu
entry_id_option 'osprober-efi-D601-A70F' {
        insmod part_gpt
        insmod fat
        set root='hd0,gpt2'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2  D601-A70F
        else
          search --no-floppy --fs-uuid --set=root D601-A70F
        fi
        chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}
### END /etc/grub.d/30_os-prober ###

As you can see, there is nothing really special going on. There isn't really a difference between GRUB and EFI, both seem to only want to load /EFI/Microsoft/Boot/bootmgfw.efi, but for some reason, GRUB gets stuck while EFI doesn't.

Does anyone know how to fix Grub to start my Windows?