I don't think it is about the specific floppy image nor about memdisk. The same floppy image and the same memdisk version (from Syslinux v.4.06) work as expected when using SYSLINUX v.4.04
The problem appears when booting with
SYSLINUX (4.06) -> memdisk (whichever version) -> same floppy image -> erompaq.exe (HP's DOS shell)
while works as expected when
SYSLINUX (4.04) -> memdisk (whichever version) -> same floppy image -> erompaq.exe (HP's DOS shell)
and it also works as expected when
SYSLINUX ((whichever version)) -> memdisk (whichever version) -> same floppy image -> FREEDOS' command.com
So, the problem appears when combining SYSLINUX 4.06 with erompaq.exe.
I even wonder if the problem could be "er
ompaq.exe" vs "eR
The question would be "what's different between SYSLINUX 4.04 and 4.06 that makes erompaq.exe fail when booted with the later".
It could also be interesting testing with Syslinux 5.xx, but that needs a little more initial work.
We need to wait for someone with the relevant hardware to test and provide feedback. ctschantz
PS: Regarding the link that Icecube
posted... FWIW, fdubcd.img v1.48 (UBCD v5.2.x) is a superfloppy image, and it doesn't need hex-editing CHS values to work correctly.