Have a look at this thread .
Best CF card in "Fixed Disk"?

And maybe try consider this https://www.tipsdotcom.com/lexar-bootit.html
(mentioned in that thread) .

Any reason for not doing it the "normal way"? That is, stick it into the system you want to use it in, do FDISK, and install DOS like you would with a real hard disk.

I found that trying to do that on a modern system fails most of the time, probably because the geometrie detected is not the same. When I got an XT-IDE for my IBM 5150, there was no way to create a bootable CF card on my Win7 machine. It would not boot in the 5150 no matter what.

Keatah wrote on 2020-05-25, 10:06:

How can I go about creating a bootable CF card for use with XT-IDE or similar interfaces? I'm familiar with the typical imaging programs and RMPREP, Rufus, and others, as well as working with Winimage and HDDGuru RawCopy.
[..]

Hi. I'd also try it on the real hardware first. In case no floppy drive is working on the target PC,
XTIDE BIOS can also be forced to boot from serial port (requires running host program on another PC and a null-modem cable).
Alternatively, you can also try setting up an HDD in an emulator. Like 86Box/PCem.
Just configure it accordingly to match your target PC (say IBM PC, XT-IDE etc) and install DOS to the HDD image.
Afterwards, run Win32DiskImager, open the image and write it onto your CF card.

Edit: In case you encounter lots of trouble, you might also consider giving DOS 7.x or FreeDOS a try.
If memory serves, these are LBA aware or do at least have a more modern boot loader.
MS-DOS 6.2x usually can handle HDDs up to 8GB in capacity only.
If the HDD in question is bigger, DOS 6.2x -or rather its FDISK program- might behave strangely.

Edit: Another program you can try is "HP USB Disk Storage Format Tool".
It's meant for USB pen drives, but maybe it will also work with an USB CF card reader..

I found you need to delete all partitions on the cf card through disk management, create new partition and format it to fat16 with disk management.

Then boot dos 6.22 floppy with a vmware, mount the cf as the hard drive, fdisk it and format again through the vmware.

Formatting it through my computer somehow also didn't let it boot for me