I recently got my hands on an IBM 340 PC (100MHz Pentium, 16MB of RAM). I'm going to wipe the disk and start fresh, but I wanted to preserve the contents of the disk should I wish to restore it to its previous state in the future.

I removed the drive and connected it to another machine where I used a Windows build of dd to create an image like so:

dd if=\\.\Volume{aef46cf9-3e3d-11de-b8c6-806d6172696f} of=raw.img bs=1M

I've found a way to mount that image in my modern PC and can browse the content and it all looks great. Just to be sure things were as expected I tried converting that raw image to a vhd format so that I could try and boot the drive in VirtualBox.

However, VirtualBox comes up with the standard "Invalid system disk" message you get when a bootable partition isn't found, so my question is whether this is a limitation of VirtualBox with an image of an old FS (I'm assuming it's FAT16) or is it likely that there's something wrong with the image and I should try to create one again before I change anything on the old hard drive?