zip disk mystery

[TaylorVcl]

I have one Iomega zip100 disk that mounts fine and another that will not mount. I am told that the system can't determine the fs type.

It is not locked.
I tried vfat, msdos, umsdos types all to no avail.
MSWindows reads the disk fine.

This is not a big deal, but it has gotten me curious. I am just wondering if anyone has had similar experience and might have a guess about what is wrong.

[evulish]

What command are you issuing?

It should be something like: mount -t vfat /dev/hdc4 /mnt/zip

[TaylorVcl]

I have tried everything under the sun:

mount /dev/hdd4 /mnt/zip
mount -t vfat /dev/hdd4 /mnt/zip
mount -t msdos /dev/hdd4 /mnt/zip

and a few other fs types.

What is really odd is that one disk works and the other doesn't, and yet they are both (ostensibly) IBM formated zip100 disks.