Installing Windows x64 on 32-bit UEFI (EFI-IA32) via GRUB [duplicate]

No problema...

Just create a USB boot device partitioned as GPT with a ESP partition formated with FAT32

Put in the USB drive the EFI structure to boot GRUB2 from 32 bits

/EFI/boot/bootia32.efi
/boot/grub/grub.cfg

put a WinPE.iso in the USB drive...
put your WindowsXX x64 iso in the USB drive...
configure GRUB2 to boot this WinPE...

I recomend Win10PE SE (http://theoven.org/index.php?topic=1336.0)

after boot from this PE iso...
mount the Windows iso as a drive (in Windows 10 just double click it),
launch WinNTSetup.exe,
fill the info in WinNtSetup from origin (the mounted Windows iso)
and destination (the drive you want to install to)

If everything went OK... the instalations is done

There is one more step you may have to do if windows is not booting...
(this can happen if firmware is trying to find bootia32.efi instead of bootx64.efi)

Boot from USB again...
format the GPT/ESP partition windows created (you must un-hide it first)
create a EFI structure (just as you did in the USB drive)
copy also GRUB2 to this partition...

(just be carefull to not touch the NTFS partition where windows is installed)

Create a GRUB2 entry to launch Windows (by BOOTMGR in the FAT32 partition is the best option)...

If you have problems you can alse copy the BOOTMGR to the NTFS partition
also the \boot folder...

and edit the BCD to point to the BOOTMGR you just copied to NTFS partition...

Hope you solve the problem...
Bye...