Hi! Although this thread is old, the findings in it cannot imho be considered 100% accurate or definitive.
My experience FWIW is reported here, trying to make it short but as accurate & to the point as possible
I have Win 98 SE w/ 80 GBytes hard disk (PATA) and a reasonably modern BIOS (i.e. LBA32 capable). I'm using the MS IO.SYS version from 2001 that is mentioned in the thread.
Have many partitions, including 3 primaries
(FAT12, FAT16 and FAT32, the last one has the "boot" flag - usually- and is the "system" partition for Windows 98 - and Win 2k Pro as well. This part crosses
the so-called 8 Gig limit.
Then an extended-LBA (type 0), containing a second FAT 32, followed by a Linux Ext2, then Linux Swap, followed by several of each Ext2, NTFS and DOS FAT partitions - not counting Ranish part manager 2.43 at the very end of the disk which is not covered by the extended partitions chain.
I used to experience the phantom
drive symptom in MS-DOS and Wiindows 98.
What I found over years of experimenting (on and off...) in relation with this thread's subj
To start I always make sure the last
partition in the chain of extended ones is a FAT-type known to MS-DOS.
This in itself however has never
prevented the bug
method which cures (not just works around) the IO.SYS volume enumeration bug for this system is making sure all extended "container" partitions (except for the most exterior one) are type 05 (NOT type 0F !
- Changing the type of any interior extended to 05 from 0Fh immediately and repeatably restores the bug.
- Steven "Phelum
" 's patches have had NO effect whatsoever on this bug within my system (neither the three of them together, nor the "206C" patch in isolation).
I'm not saying Steven's patch(es) are useless for everybody, just that they're not needed or helpful on my system
Sincerely hoping this feedback can help anybody who wished to have another look at this bug (I haven't even tried to disassemble IO.SYS). I would appreciate R.Loew's comment in particular, whether he thinks I am secure from the unspecified (other?) bug(s) he is aware of (and considering I have no use for LBA 48).
As a final note, other DOSes (i.e. non-MS) which are FAT32 and LBA-aware have no problems enumerating and mounting all my FAT partitions, whatever combination of 05/0F types internal extended partitions are given. Nor have Linux or even MS Windows 2000 SP4 any problems! However for MS-DOS (and Windows 9x) compatibility my advice based on this experience is to have all extended containers typed 05
except of course the priamry extended LBA which must be type 0Fh
This post has been edited by Czerno: 21 September 2011 - 08:06 AM