This is the only tutorial from BigReds that works, boots and installs any WIN 7, 8.1, 10 or AIO (All in one) OS.iso with UEFI support in Legacy and UEFI mode on one USB (NTFS – Active/FAT32 – Hiden partition) if your Motherboard has UEFI/EFI BIOS support. In NTFS format one file is allowed to be bigger than 4 GB and this tutorial is superb if install.wim is bigger, where FAT32 limit is 4 GB max.
Note that the OS.iso will also need to support UEFI otherwise this won’t work!
Also, if you are installing the OS in UEFI mode you will need to format the hard drive you are installing to into GPT if you use MBR you can only install the OS in legacy mode.
Also, note if you are using 32 bit UEFI OS.iso it will only boot into UEFI mode if your motherboard has an 32 bit UEFI BIOS and those motherboards are rare.
If your AIO OS.iso has 32 bit and 64 bit entries of windows editions instead of making a source folder only on the hidden FAT32 partition like on the video, you need to create an x64 and x86 folder and in both folders, you need to create a folder called sources and in each of those sources folders you need to copy the 32 bit or 64 bit boot.wim file from the OS.iso! So x86sources needs the 32 bit boot.wim and the x64 needs the 64 bit boot.wim copied inside. If you don’t do it correct then the entries in the windows installation will not be correct for UEFI boot mode.
To test this after completing the process you need to go into the BIOS settings and chose either:
– Boot in Legacy and UEFI
– Boot in Legacy first or UEFI first
When you do that, you can choose Legacy or UEFI in the boot options menu like on my video.
Also, make sure you have enough space on the primary and the hidden partition on the USB drive while doing this.