I formatted six USB flash drives with Rufus. Three are unbranded (2GB - $1.50 each), purchased when I was visiting an electronics flea market. The other three are the ubiquitous SanDisk Cruzer Glide (16GB). Rufus formats USB flash drives: https://www.majorgeeks.com/files/details/rufus.html Using the app PeToUSB, I installed BartPE on all six flash drives. The unbranded flash drives boot normally. The SanDisk drives will not boot. All six are new. If you are not familiar with PeToUSB read this: https://www.softpedia.com/get/System/Boot-Manager-Disk/PeToUSB.shtml The only difference between the unbranded (2GB) and SanDisk drives (16GB) is capacity. There is nothing on all six drives, except the BartPE folders and files. I hope a forum member can tell me why the SanDisk drives won't boot and how to fix the problem.
lemonlime, Try putting a Win10 ISO on the SanDisk UFD with Rufus. I have some 16 GB SanDisk UFDs and Win10 boots from the UFD.
Another thing you can try is to choose the DD option when flashing the problem drives. Rufus often gives you a choice, and recommends the non-DD option, because then you can use the remaining free space on the drive for regular file storage purposes. However, DD boots better. If you use Belena Etcher, it always writes the image in DD format.
To create a "perfect app" is probably impossible. Yesterday, I found a flash drive formatting and booting app that should get six stars (not five) in all reviews! RMPrepUSB fully integrates functions that formally required several apps. Anyone with intermediate level computer skills can use RMPrepUSB. All three of those "unbootable" SanDisk flash drives were properly formatted and made bootable with BartPE. SanDisk drives were tested on four computers. Booting into BartPE was smooth and quick. RMPrepUSB is freeware. Get it now before it becomes shareware. https://www.rmprepusb.com/ https://www.majorgeeks.com/files/details/rmprepusb.html