If XP can see the ZIP as a disk in XP's disk management tool, then you might
be able to do something with the ZIP.  The most obvious thing would be to
try XP's CHKDSK /F on the ZIP.

Other software options are listed below.

But, if XP can not see the disk, then the ZIP cartridge could be physically
damaged, or the ZIP drive could be damaged.

So, your first task is to determine if the problem is hardware related.  The
easiest way to test the ZIP cartridge is to try to read it in another PC
with a known-good ZIP drive.

Unfortunately, I have had some ZIP cartridges go bad over the 10 or so years
I have used them, and I was never able to recover data from them.  I have
found write-once CDs (CD-R) to be much more reliable.

If the cartridge is basically OK, but there are a few bad spots on the
cartridge, it might be possible to read/copy most of the information via  a
program like "badcopy":  http://www.jufsoft.com/  They offer a free
evaluation copy.  It migth be worth a try.

Other programs in this class include "unstopable copier" and "raw copy",
both at:  http://www.roadkil.net/downloads.html

Other recovery options can be found at:
http://www.majorgeeks.com/downloads38.html   But, most of these are for
recovering accidentally deleted files.

There are also imaging programs that can perform a bit-by-bit copy of one
disk into an image on another disk.  If the ZIP is accessible, but not
readable, one of those might preserve the data.  Some can also mount images
as if they were disks, then you could attack the image with software to
attempt to recover files.  However, many imaging programs first check for
disk integrity and will refuse to make an image, if the disk has problems.
One that might make an image of a bad disk is
http://www.data-recovery-software.net/

Look here for other realted programs:
http://www.majorgeeks.com/downloads3.html

Try booting to xp cd,press r For recovery,press enter key for password,select
1 For C:  Type:DiskPart  In DiskPart,the drive should be listed,maybe delete
the partition,create one,press ESC key,type:FORMAT D: /FS:ntfs  Or type:
CHKDSK D: /R  D: being the zip drive.The R Repairs bad sectors & fixes the hd
where available.

You may find something here that will help..

http://zip-disk-recovery.qarchive.org/

Thanks - I ran the chkdsk and it repaired everything.  I was not sure that I
still had a CHKDSK feature within Win XP