I think because of the size of your image you have to use NTFS.  When you go to format the USB drive it may give you only NTFS as an option.

support.microsoft.com/.../you-cannot-start-a-computer-from-a-usb-flash-drive-that-is-formatted-to-use-the-fat32-file-system

Your backUp file wouldn't be that big but you still will need to go with NTFS and be careful those usb flash drives aren't the best  to use for things like that

You have to use DISKPART to format USB Media and make the partition Active.  FAT32 will not handle files larger than 4 gigs.

That makes it unsuitable for images of operating systems that tend to be 12 gigs or larger.  Same with ISO files aka DVD images can be 4.7 gigs and larger with dual layer.

https://technet.microsoft.com/en-us/library/jj200124%28v=ws.11%29.aspx

DISKPART

LIST DISK

SELECT DISK

CLEAN

FORMAT FS=NTFS

ACTIVE

http://www.supertalent.com/datasheets/Resetting%20USB%20drive%20using%20Windows%20Diskpart-V1.pdf

SpeedStep,

When I use Macrium Reflect Free to create the System Image on a USB stick, Macrium will create the Image as a .mcimg file. In the future, when I want to restore to the System Image, I plan to use Macrium to perform the restore.

Given this scenario, the USB stick does not have to be bootable, right? Is this correct or have I got it wrong?

And, if the USB stick does not have to be bootable, then I do not need to use DISKPART, right? Is this correct or do I also have this wrong?

Thanks

The USB Stick doesn't need to be bootable, just formatted correctly.

The issue being that a Fat32 formatted stick will not save an image file larger than 4 gigs. Every windows VISTA or 7 or 8 or 10 image would be at least 12 gigs if not more. Norton Ghost handled this with the - split command to break images into 2048 meg chunks that can span media aka more than one disk or flash drive.

OK. Now I know... the USB stick does not have to be bootable. Thanks.

You say it needs to be formatted correctly. What's the correct formatting? It comes from the store (new) as FAT32. Does it need to remain FAT32? Or, does it need to be NTFS? Or, some other format?

If it needs to be NTFS, I can accomplish this by using Windows Explorer (right click > format), right?

You need to format it to NTFS,