I don't know.
What happens when you disable the FDD or controller in the device manager?
Is your drive A: in compatiblity mode then?

I actually don't know, but I currently am in the middle of something else on the computer: I'm trying to optimize a DOS boot/config floppy with QEMM. I'm having a problem with DBLSPACE: it's eating over 100k of DOS memory. I don't want or need it. I'm aware of a setting in MSDOS.SYS to do it, but when I open the file, the only line is ";SYS." Let me see if I can still get it to work anyway.

It displayed a corrupt registry error but otherwise seems to work. I'll try to access a DriveSpace-compressed floppy and, if it works, run OPTIMIZE again. 😀

Just remove / rename DBLSPACE.BIN or DRVSPACE.BIN

I couldn't access two DriveSpace floppies, so I'll use Stacker instead. BTW, how do I get Stacker to automatically mount a floppy? Also, when it compresses a floppy, it adds a driver to mount the floppy outside of Stacker. As far as I'm concerned, it's a waste of space. How do I disable that feature?

Disruptor: the MSDOS.SYS setting works but causes Windows to display a Registry Corrupt error on startup. 🙁 Other setups work, though.