A screenshot of freedos defrag running in DOSBox-X, with an error message reading "Disk read error" https://digipres.club/system/media_attachments/files/111/881/115/013/560/412/original/53eaeb16262e2be1.png
even freedos defrag in DOSBox won't work! probably because it's trying to do low-level access and DOSBox isn't giving it that level of access.