NEW for 2020: Many systems these days are UEFI-only. Once you have made your E2B USB drive, I suggest you add a 2nd FAT32 partition containing the new a1ive grub2 File Manager for direct UEFI-booting from the ISO, WIM, VHD and IMG files on your E2B drive.
Use the 'Guide' below to help you choose the best way to set up and use an E2B USB drive...
1. Type of USB Drive (Fixed v. Removable USB drive)
When booting Windows-based payloads, it is important to know what type of USB drive you have.
Use RMPrepUSB to check if your USB drive is the Fixed type (e.g. USB Hard Disk) or Removable type (*recommended).
E2B is easier to use if the drive is the Removable USB type (e.g. for Windows ISOs), but you can use a USB HDD if you wish (but some changes may be required when booting Windows Install ISOs, see here).
Note that some USB Flash drives can be very slow (even some 'fast' USB 3.0 ones such as Lexar P20!). I highly recommend the SanDisk Cruzer Extreme USB 3.0 Removable USB drive for E2B - for larger sizes, speed and robustness, a cheap SSD HDD in a fast USB 3.0 non-UASP drive caddy is great!
Write-Protected drives - When booting from an E2B drive, the drive must not be write-protected. However, when connecting it to a Windows\Linux system to run software from the drive, it is useful to write-protect the USB drive to prevent infection from the user's OS. Write-Protected USB 3 drives are available from FlashBlu, Kanguru or Netac (Netac U335 is not recommended due to reliability issues in my experience).
2. USB Drive size
Many BIOSes in PCs and Notebooks have a 137GB limit (driver bug) for USB drives (even recent BIOSes!) - any files placed beyond that point on the USB disk cannot be accessed on some systems (under grub4dos which uses the system BIOS). This means that the E2B partition must be the first partition on the USB drive and should not exceed 137GB to ensure it will work correctly on these buggy systems.
Use the big red button in the Make_E2B.exe GUI or run the \MAKE_E2B_USB_DRIVE (run as admin).cmd script. See here.
Unless you are an expert and have very specific requirements, I recommend that you always use NTFS for your E2B USB drive and not FAT32 or exFAT.
You will still be able to UEFI-boot from .imgPTN files even if your USB drive is formatted as NTFS.
I do not recommend exFAT for E2B (though it should work OK for most purposes) because some Operating Systems cannot access exFAT partitions.
Also, SWITCH_E2B.exe is used with .imgPTN files and it is only fully compatible when used on NTFS E2B drives.
E2B can work on ext2/3/4 drives too, but it is not supported because of compatibility issues with Windows and DOS.
Tip: If you work with UEFI-only systems, I recommend you read eBook #3 which describes how to add a 2nd FAT32 partition to your E2B USB drive so that you can UEFI-boot to WinPE and then you do not need to MBR-boot to select a .imgPTN file.
5. Adding Payloads
Always check the list here first for your particular payload and any special instructions.
For MBR-booting only, copy your payload file(s) to any E2B menu folder.
If you want to UEFI-boot and MBR-boot, make a FAT32 .imgPTN file using the MPI Tool Kit.
Always run \MAKE_THIS_DRIVE_CONTIGUOUS.cmd before booting.
UEFI-booting using FAT32 .imgPTN files will only work if the payload supports it and it contains UEFI-boot files.
If you want the second partition on the E2B USB drive to remain accessible, use a file extension of .imgPTN23 to keep partitions 2 and 3 (if they exist).
MBR-booting from a Windows .ISO file may not work correctly if you have a Fixed disk type of E2B USB drive - use or update to E2B v1.A8 or later.
Windows-based .imgPTN files will work on both Removable and Fixed disks.
Some payloads do not support UEFI-booting, but if you use the grub2 menu system, it is possible to UEFI-boot to many linux ISOs which don't normally support UEFI-booting. For Secure Boot, if using the E2B grub2 menu system, the 2nd partition must be FAT32 not NTFS.
Below are listed some typical payload files - it is important to know what type of USB drive you have first (Removable or Fixed) because this can affect how they boot...
All types of E2B drive (Removable and Fixed types):
Linux ISOs (MBR booting) - Copy the ISO to any of the standard menu folders (e.g. \_ISO\MAINMENU or \_ISO\LINUX).
Linux ISOs (UEFI-booting) - Copy the .imgPTN file to any of the standard menu folders (e.g. \_ISO\MAINMENU or \_ISO\LINUX).
Puppy Linux ISOs - use the .isopup file extension
Mac puppy - use .isomacpup file extension
Linux + persistence - Find and read the nearest matching .mnu file in the \_ISO\docs\Sample mnu Files\Linux folder.
Windows Vista/7/8/10+ Install ISOs (MBR-booting + UEFI-booting) - Use as .ISO or convert a working bootable USB drive or ISO to a FAT32 .imgPTN file. Copy the .imgPTN file to any of the standard menu folders (e.g. \_ISO\MAINMENU or \_ISO\WIN) or to the correct \_ISO\WINDOWS\WINxxx folder.
Windows XP 32-bit Install ISOs (MBR-booting) - Copy to \_ISO\WINDOWS\XP folder
Windows To Go VHD - Copy the .VHD file to any of the standard menu folders (e.g. \_ISO\MAINMENU or \_ISO\WIN).
WinPE .WIM file - Copy the file to any of the standard menu folders (e.g. \_ISO\MAINMENU or \_ISO\WIN).
ERD Commander 2005/2007/MSDaRT5 - use the .isomemF01 or .isomemwinv file extension or use .isoDPMS or the ERD5_DPMS.mnu sample file.
BartPE - use .isomemF01 or .isomemwinv file extension