And I will do the same. I am not replying for the current message because I don't know the answer. I just want to tell a similar story about the disorder of my 3.5'' floppy driver. Two weeks ago I deleted some old files on about 5 floppy diskes, then copy some files from another computer. I changed the floppy driver and the cable with another.
Same problem is still there.
I am using Windows95 in my computer. I tried the method given by David Roesch in the response number 2. The green light on the floppy driver on, and the floppy disk inside run for a while. Either the selected capacity is not valid for this disk, or the disk is damaged and may need to be replaced. I am sure the floppy disk is not damaged and the selected capacity is valid.