Ok, kinda “fresh” post, now about windows.
How is that simple to just see what is going on in /boot/efi partition right from windows, as simple as from *nix, right? NO!
diskpart list volume (find system one, there would be EFI bootloader) assign letter x:
according https://technet.microsoft.com/en-us/library/hh825686.aspx should got flag 0x0000000000000001
So you need to manually give it a letter, as from above.
And as far as it system partition, to reach this you should act like a su, so to see something in GUI, just reset explorer in admin mode:
taskkill /im explorer.exe /f explorer.exe
Now you good to go, simple as that.