Phantom extra partition - how to cure?

I have a delightfully garbled problem:
Windows 98 sees a non-existing partition!


MY SYSTEM

Tosh laptop, Win98 FE + Linux + NetBSD on 19GB HD,
partitions as follows:
C: /dev/hda1 Primary 2900MB Windows 98 + apps
D: /dev/hda2 Primary 50MB DOS (bootable with some tricks, FAT16)
E: /dev/hda5 Logical 500MB temporary files
F: /dev/hda6 Logical 400MB Windows swap (FAT16)
G: /dev/hda7 Logical 1500MB hot work files + application data
H: /dev/hda8 Logical 5000MB cold work files, software installers, etc.
-- /dev/hda9 Logical 300MB Linux Swap
-- /dev/hda10Logical 3950MB Linux Root
-- /dev/hda11Logical 3100MB extra, usage varies
-- /dev/hda4 Primary 1600MB NetBSD "slice", primary, 1600MB.



THE SYMPTOMS

a) Windows always refused to assign letters to partitions in this
sequence, although they are laid out like this on the hard disk. I
fixed it with Vadim Burtyanski's "Letter Assigner", a program that
reassigns letters ad lib on boot. No problem there.

b) Rebooting after a BSOD during a defrag ("Fatal Error: Missing
Segment") Windows discovered a non-existent "unformatted" partition of
nearly 5GB.
- a D: drive popped up in "My Computer"
- the former D: drive got bumped to I:
- all other drives assumed preposterous identities untill reassigned
by means of Letter Assigner
- Letter Assigner could not ressign D: to anything else, claiming it
could not get "correct information".
- now D: drive would not open on clicking. Dialog offered to format.
Format dialog claimed the partition size was 4879MB, so now the sum of
partitions adds to 24GB, cool, 'cept this is a 19GB drive.

c) NetBSD and Linux partitions still alive and well.



ATTEMPTED CURES

- restored the partition table from back up
- refreshed drive letter reassignment
- erased and reformatted Linux and NetBSD partitions, reinstalled
- erased and reformatted the large "cold" data partition on H:

Windows, Linux, and NetBSD all still seem to work, yet Windows
stubbornly sees an extra, nonexistent, unformatted 4879MB partition.

Give or take 10MB, Windows seems to have "rediscovered" the H:
partition and to have assigned it both H: and D:.

I suspect the crash left some fake "marks" on the partition, which do
not correspond to the partition table.



MY QUESTIONS

1) Is this kind of issue typical of a defrag crash?

2) Where does Windows get its (wrong) info from,
if not from the partition table?

2) Is there any workaround, short of reformatting the whole drive?
E.g., what if I emptied and reformatted each Windows partition?


TIA!! Any hint will be appreciated!

Filippo N1JPR
Milan, Italy