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Installing OS/2 with FAT32 around

By Darryl Sperber ©October 2000 FAT32.IFS: http://www.os2ss.com/information/kelder/#FAT32

I have a C: drive (FAT) containing Win98, and a D: drive (HPFS) for OS/2. I want to convert the C: drive to FAT32 and still have OS/2 see it. The question is, how can I convert C: to FAT32 without changing the drive letters for either Win98 or OS/2? And how can I make that FAT32 partition visible to OS/2?

I'm trying to put OS/2 onto a T20 thinkpad. I've used Partition Magic on the FAT32, bringing windoze 98 down to a reasonable size. I've made room for Boot Manager. I've added logical partitions (i.e. an extended partition subdivided into logical partitions) for OS/2 and its data drives, and I've PTEdited the extended partition type from 0F to 05. I want at the end to have the windoze FAT32 drive come out as the highest drive letter as seen by OS/2. Main query: What to do?

I had a perfectly functional multi-boot environment using Boot Manager, including Win98 on a FAT32 partition, and OS/2 on an HPFS partition. OS/2 was on C (as seen by OS/2), and using FAT32.IFS I was able to access the FAT32 partition as D. I recently upgraded Warp 4 to fixpack 14 and it appeared to finish successfully. Then I used FDISK to review my partition sizes but did not make any changes. Now I can't boot OS/2 from Boot Manager. The boot process appears to start properly, but then it stops cold giving me the message "OS/2 is unable to operate your hard drive". What happened, and how can I correct it?

How can OS/2 peacefully survive in a Boot Manager environment in which FAT32 partitions exist, and in the simplest case in which Win9x is installed on a primary FAT32 partition on the first hard drive (seen as C) with OS/2 on the logical second partition (ideally seen as D)?

As simple as this goal sounds, and as common as this need is, the problems and confusion involved with achieving this goal have, until now, been remarkably overwhelming. And more recently, changes by IBM (beginning in fixpack 13) in their attempt to converge the WSeB kernel with Warp 4, and especially insofar as FAT32 recognition is concerned, have proven to be extremely problematic for users... making bad things even worse for anybody who's upgraded to fixpack 13 or 14 in a FAT32 environment.

This article has as its goal the providing of the "recipe" for successfully installing OS/2 in a FAT32 environment, supporting two conceptually different and distinct final target configurations. Through the magic of DaniDASD.DMD, it is now even possible to end up with exactly the same drive letters for all FAT16 and FAT32 partitions as seen by both Win98 and OS/2.

For the sake of discussion, let's propose a very simple demonstration configuration. You have a large hard drive that you've divided into three partitions:

Boot Manager
FAT32 primary Win98
FAT16 logical OS/2
FAT16 logical data for OS/2

And let us state as the "Holy Grail" the goal of having identical low drive letters for FAT16 and FAT32 primary/logical partitions, as viewed by both Win98 and OS/2.

The key factor here is that you have at least one non-hidden FAT32 partition present, and it is IN FRONT OF the bootable OS/2 partition from the perspective of the standard primary/logical lettering algorithm, assuming FAT32 would be lettered just like FAT16 and HPFS. This perspective is referred to as "FAT32-aware", and has only recently become available as an option for OS/2 through the magic of DaniDASD.DMD coupled with IBM's "new" FDISK and "new" Boot Manager.

In contrast, OS/2 has in the past never been able to recognize FAT32 partitions, other than as Type 0B or Type 0C partitions. It certainly has never before (until recently) assigned a drive letter to a FAT32 partition via FDISK or any other component. And this perspective is referred to as "FAT32-blind".

And that brings us to our first problem, namely that OS/2 from its earliest GA days has been FAT32-blind, at least up through FP9 of Warp 4. Specifically, FDISK and its resulting Boot Manager up to that point were both FAT32-blind, and these are referred to in this article as the "old" FDISK and the "old" Boot Manager.

Beginning with FP10 IBM changed FDISK to be "sort of" FAT32-aware although the rest of OS/2 was still left fully FAT32-blind. This was potentially harmful, but generally benign. If FDISK were simply used to view or configure partitions, it did not modify an existing "old" Boot Manager from its FAT32-blind form and thus did no harm. But if asked to delete and re-create Boot Manager it would create it as FAT32-aware (i.e. "new" Boot Manager), thus causing pre-existing OS/2 partitions to become non-bootable in a FAT32 environment by virtue of the resulting up-shift of the OS/2 partition drive letter as shown on the Boot Manager menu.

It is honestly quite surprising that more OS/2 users did not have boot problems beginning with FP10, assuming they created Boot Manager using that version of FDISK. Perhaps there were not nearly as many FAT32 environments back then in which the problems of using the "new" Boot Manager would show up. Or maybe the delete/re-create of Boot Manager was quite rare on pre-existing systems, since this action wasn't strictly necessary when adding new hard drives... the most common form of upgrade.

But the real crisis for users came with FP13. At that time IBM changed FDISK to be "fully and completely and automatically and quietly" FAT32-aware, although again the rest of OS/2 (specifically OS2DASD.DMD) was remarkably still left fully FAT32-blind! FDISK now automatically (and without warning or option to override) converted any discovered FAT32-blind "old" Boot Manager to a FAT32-aware "new" version, by virtue of the mere opening and closing of the FDISK program... even if it was not asked to do anything, and even if it was not specifically asked to delete and re-create Boot Manager!

This is referred to as the "new" FDISK and the "new" Boot Manager throughout this article. And this "new" FDISK which suddenly and without notice converts a FAT32-blind Boot Manager to a FAT32-aware Boot Manager is therefore very dangerous when used in a FAT32 environment, unless the installation "recipe" described later is followed so as to build a truly and fully FAT32-aware, and therefore "new" FDISK compatible, OS/2.

At this moment, IBM is working on a solution to this now-recognized chaos they have wrought on the multi-boot OS/2 user community with their recent versions of FAT32-aware FDISK and "incompatible" FAT32-blind OS2DASD.DMD. This is confirmed by IBM to be THE current "hot" item on the problem list for resolution (hopefully) with FP15.

But in the meantime, there are workarounds and circumventions available for FAT32 users, and that's what this article is all about.

What's the plan?

Plan (1) is FAT32-aware (based on the use of DaniDASD.DMD and the FAT32.IFS product), with the primary FAT32 partition being assigned a low drive letter of C in both Win98 and OS/2. The logical partitions are then given letters of D and E.

Plan (2) is FAT32-blind, with the OS/2 visible partitions being given low drive letters of C and D. Through the use of the FAT32.IFS product the primary FAT32 partition is assigned a letter after the last OS/2 visible partition (as if it were a logical partition on a "virtual drive"), namely E.

Note that there are valid justifications for both types of target configuration, although Plan (1) seems intuitively much simpler to live with. And both configurations use the FAT32.IFS product to give read/write access to the FAT32 partition... no matter whether the letter given is low or high.

Plan (1) utilizes DaniDASD.DMD instead of OS2DASD.DMD to give low drive letters to FAT32, FAT16, and HPFS partitions equally according to standard primary/logical partition lettering rules.

Plan (2) uses OS2DASD.DMD and PARTFILT.FLT to give high drive letters to FAT16 and HPFS primary/logical partitions first, followed by FAT32 partitions.

Plan (1) has a "new" Boot Manager built by the "new" FDISK, while Plan (2) has an "old" Boot Manager built by the "old" FDISK.

The key trick to the success of Plan (1) is that if you want to end up FAT32-aware after installation you must first temporarily allocate one small 15meg FAT16 "placeholder" partition IN FRONT OF your OS/2 bootable partition, to exist only during the OS/2 install. It will be deleted after the installation is finished, its letter to be replaced by assigning a letter to the FAT32 partition.

Note that in more elaborate configurations, you must allocate one such temporary proxy partition for each FAT32 primary/logical partition which will ultimately be given a drive letter in front of the OS/2 bootable partition. All of these temporary placeholder partitions will exist during the OS/2 installation process, to be simultaneously deleted at the end of the process, being simultaneously replaced by FAT32 partitions which will receive the identical drive letters as the placeholders originally had.

One more consideration to Plan (1) concerns HPFS partitions. Since HPFS is invisible to Win98, it seems ideally appropriate to position any HPFS partitions AFTER the last FAT16 and FAT32 partition (according to standard primary/logical partition lettering rules). That way HPFS partitions will be given unique high drive letters for OS/2 only, with all the earlier FAT16 and FAT32 partitions being given identical low drive letters for both Win98 and OS/2. The result is maximum possible drive letter similarity in the Win98 and OS/2 environments, with minimum letter-shuffling confusion.

Okay, what's the recipe for Plan (1)?

(1) copy of DaniDASD.DMD obtained via email from her, at

[remove nospam] Daniela Engert <daninospam@ngrtnospam.de>

and FAT32.IFS, obtained from:

http://www.os2ss.com/information/kelder/index.html

(2) initial GA install diskettes (modified for any new/updated
IDE/SCSI drivers you require for hardware, along with
config.sys modified to have SET COPYFROMFLOPPY=1).

(3) "old" (FP9 or older, or Warp Connect) bootable utility
diskette set.

(4) "new" (FP10 or more recent) bootable utility diskette set,
modified to contain DaniDASD.DMD on diskette 1,
and an updated config.sys that names DaniDASD.DMD
instead of OS2DASD.DMD.

Installation steps.

If you currently have a Boot Manager built with a "new" FAT32-aware FDISK you must use the "old" FDISK to delete that partition, and then re-create it using the "old" FDISK. This is MANDATORY for the following approach to work.

Everything you do during your initial install must be FAT32-blind!!! That includes the use of OS2DASD.DMD (not DaniDASD.DMD), and the FAT32-blind GA version of FDISK from the CD (not a "new" FDISK).

Later steps will convert your installed OS/2 to be FAT32-aware, including the re-creation of Boot Manager using a more recent FAT32-aware FDISK. However your initial installation cannot be that way (since the CD version of FDISK is FAT32-blind and there's no way to get around that).

(2) Use this "old" FDISK (or Partition Magic, if you want to) to create one small logical FAT16 "placeholder" partition, located right after your primary FAT32 partition and before your installable target OS/2 partition.

Again, in more complex multi-FAT32 partition environments, you'll need one placeholder partition for each FAT32 partition which will receive a drive letter before your OS/2 boot partition.

Thus your FAT32-blind configuration now looks like this:

Initially, this placeholder partition will occupy FAT32-blind drive letter C, making your target installable OS/2 partition appear as D. This is as it MUST be for the initial FAT32-blind installation to succeed, and this is how you're going to end up as well even after becoming FAT32-aware. But for now, you need the placeholder C partition to exist as a proxy for the FAT32 C.

Ultimately, when everything is finished, the final step in the recipe will delete this dummy placeholder partition, activate lettering for FAT32 through the use of DaniDASD.DMD instead of OS2DASD.DMD, and re-create Boot Manager using a "new" FAT32-aware FDISK. At that moment your FAT32 partition will become FAT32-aware C, instead of this FAT32-blind placeholder C. And your OS/2 partition will still remain as D, and you will have achieved your goal.

(3) Do the GA Warp 4 install using your original GA installation diskettes. Select the "advanced" method, and FDISK (GA FAT32-blind version from the CD will be used) will be opened. Choose D as your target installable partition. This will cause FAT32-blind D to be installed as the bootable partition letter on the "old" Boot Manager menu, as it must also be when we become FAT32-aware.

Naturally, you should modify diskette 1 and config.sys to include any other device drivers you require (e.g. non-standard SCSI drivers, updated large IDE drive drivers, etc.), and also to have SET COPYFROMFLOPPY=1 (for Warp 4).

After basic installation (i.e. while still FAT32-blind), you can re-install all of your customization and vendor software. Or, you can defer this process until after converting to your intended FAT32-aware environment.

(4) For convenience in the final steps about to come, perform the following items now, while running under WPS and PM in an operating OS/2:

(a) copy DaniDASD.DMD to D:\OS2\BOOT on your hard drive

(b) follow the steps for installation of FAT32.IFS, by copying the following files to your \OS2 directory:

FAT32.IFS
CACHEF32.EXE
F32STAT.EXE
MONITOR.EXE

copy the following file to your \OS2\DLL directory:

UFAT32.DLL

Do NOT install PARTFILT.FLT. You won't need it, as DaniDASD.DMD performs the same functionality of assigning letters to FAT32 partitions, except that they're given low letters as we want.

(c) create a copy of D:\CONFIG.SYS, calling it CONFIG.F32.

Modify CONFIG.F32 to name DaniDASD.DMD instead of OS2DASD.DMD.

Make the following additions to CONFIG.F32, as part of the installation of FAT32.IFS (you should refer to its installation instructions for additional options and notes):

IFS=x:\OS2\FAT32.IFS
(Install this one AFTER IFS=HPFS.IFS)

CALL=x:\OS2\CACHEF32.EXE
-> Make sure this is a CALL and NOT a RUN.

Again, refer to the FAT32.TXT documentation, in the OS2FAT32.ZIP package, for more details.

Remember that diskette 1 of this modified diskette set must include DaniDASD.DMD, and config.sys on diskette 1 must be modified to name DaniDASD.DMD instead of OS2DASD.DMD. You do not want FAT32.IFS on this diskette set... only DaniDASD.DMD.

Open the "new" FAT32-aware FDISK (from the 4th diskette) and delete the placeholder partition.

Also delete the Boot Manager partition (initially created by the "old" FDISK) and then create it again, using this "new" FDISK. Your FAT32-aware drive letters should now have appeared, and the letter of your OS/2 bootable partition should still be D, exactly as it was when you just installed it while under the "old" FAT32-blind Boot Manager.

Exit FDISK (naturally, make sure you save your changes), and you'll get the usual "drive letters changed, C-A-D".

Go ahead and reboot... from these same modified utility diskettes again.

(6) Open the "new" FDISK from diskette 4 again. You should still see your partitions lettered exactly as you want, with the FAT32 partition given a letter of C and shown with a type of "FAT32".

Again, your bootable OS/2 partition should have the exact same letter of D as it had when you did the GA install and the installed OS/2 was originally added to the "old" Boot Manager menu.

You've simply swapped the now-lettered FAT32 partition for the previous proxy partition, which has now been deleted and returned to free space. This is really the key concept to why this approach works, along with the true magic of DaniDASD.DMD and FAT32.IFS, coupled with IBM's FAT32-aware "new" FDISK and its "new" Boot Manager.

Exit FDISK.

(7) While still booted from diskette and before you re-boot from the hard drive, modify the installed OS/2 system(s) on your hard drive (D, in your case) as follows:

(1) rename D:\CONFIG.SYS to D:\CONFIG.OLD

(2) rename D:\CONFIG.F32 to D:\CONFIG.SYS

Your OS/2 partition should show a letter of D on the Boot Manager menu, which exactly matches your original FAT32-blind installable target letter.

Your Win98 bootable partition should show as C, with a partition type of FAT32.

This is as it should be.

Selecting OS/2 from the "new" Boot Manager menu, you should have no problem booting and continuing on with your vendor software reinstall and customization process (if you've deferred it until now).

Once into the booted OS/2, all of your partitions (FAT32, FAT16, and HPFS) should now be low lettered exactly as you'd expect (through DaniDASD.DMD) given that all of them are now treated identically from the point of view of primary/logical lettering rules.

And your FAT32 partition will also have been endowed with full read/write capability (through FAT32.IFS), including complete support for long Win9x-format long file names. FAT32 is treated just like HPFS for long file names, from a user-interface perspective.

If you've deferred vendor software installation and other customization, you can proceed with that effort now.

Fine. So much for Plan (1).

The significant difference from Plan (1) is that you do NOT want placeholder partitions during the install. In such a configuration, the OS/2 installable partition will be seen as FAT32-blind C, which is what you want to end up with.

Also, you will NOT perform any of the steps involving DaniDASD.DMD. You are NOT going to be using FAT32-aware DaniDASD.DMD! Instead, you will continue to use the standard IBM FAT32-blind OS2DASD.DMD.

Also, AND THIS IS CRITICAL, you will ABSOLUTELY NOT delete/re-create Boot Manager using the "new" FDISK. In fact, you are going to have to stick with the "old" FDISK and the "old" Boot Manager forever!

Repeat: do NOT use the "new" FDISK ever! Only use the "old" FAT32-blind FDISK.

Finally, your installation of the FAT32.IFS product WILL include PARTFILT.FLT, as this is the component which gives high letters to FAT32 partitions... which you need in the FAT32-blind environment.

NOTES:

In other words, ALL installs must be done while still FAT32-blind. You can only convert to FAT32-aware at the very end of ALL the OS/2 installs, and then each of the newly installed OS/2 systems must be DaniDASD.DMD-enabled together (i.e. step (7) performed for each of them), since you're going to a "new" Boot Manager and cannot mix FAT32-blind and FAT32-aware worlds.

(2) In more complex configurations involving multiple hard drives, multiple primary/logical partitions, multiple FAT32 partitions, etc., you must allocate one temporary placeholder partition for each FAT32 partition which will be lettered in front of the OS/2 bootable partition(s), in order to perform the basic OS/2 installation.

Then at step (5), all of these proxy partitions will be deleted together and returned to free space. The multiple FAT32 partitions will then take all their places, from a drive lettering perspective, leaving your OS/2 partitions lettered exactly as they were originally.

(3) The modified utility diskettes, of vintage FP10 or newer, should be used for all partition-related and formatting functions going forward. Once you become FAT32-aware and install the "new" Boot Manager, you absolutely MUST always use the "new" FDISK.

Disk 1 of this set was modified to contain DaniDASD.DMD and a modified config.sys (naming DaniDASD.DMD instead of OS2DASD.DMD). And disk 4 of this set contains the "new" FDISK. All of this matches your new FAT32-aware drive letters implicit in your FAT32-blind install using placeholder partitions.

Note that FAT32.IFS is NOT on these diskettes (no room, and it's not really necessary) so that the FAT32 partitions will be given letters by DaniDASD.DMD but will not have any read/write access. You'll only be able to manipulate your FAT16 and HPFS partitions.

(4) Although I can't speak from firsthand experience, the use of LVM instead of the "new" FDISK should also work, in a WSeB environment, as LVM and WSeB are FAT32-aware out of the box.

But the Warp 4 and Warp Connect systems must be installed first, in a FAT32-blind environment with the "old" Boot Manager still active.

In other words, un-verified theory has it that LVM can be used to re-create the "new" FAT32-aware Boot Manager rather than the "new" FDISK, after defining the logical view of partitions to exactly match the FAT32-aware perspective anticipated by DaniDASD.DMD. Once that's done, WSeB itself can now be installed to another FAT32-aware partition letter of its own. In fact, WSeB can ONLY be installed after Boot Manager has been built by LVM, as I understand it.

When booting to Warp Connect or Warp 4 from an LVM-produced Boot Manager menu, as long as the letters for the OS/2 partitions match what was in effect during the FAT32-blind install, it would stand to reason that WSeB can be added to the FAT32-aware multi-boot environment as well, as long as the other OS/2 partitions are installed first using the FAT32-blind method I described previously.

(5) The "install from scratch" approach assumes you already have FAT32 on your system, and you're willing to re-install OS/2 using a method which will end up the way you want it to. This is the only way you can go, if you already have existing FAT32 partitions.

However if you're "blessed" by still having your Win98 partition on FAT16 (i.e. it is currently seen as C, and your Warp partition is currently seen as D), then you can "cut right to the chase" when you decide to convert from FAT16 to FAT32.

You don't need to reinstall OS/2 from scratch in this situation... you only need to make it FAT32-aware at the same moment as your FAT16 partition becomes FAT32. This is precisely because your current, existing OS/2 partition letter is already EXACTLY what you want to end up with after C becomes FAT32. No placeholder partition technique is needed... your goal of FAT32-aware D is already a FAT32-blind D!

Assuming you already have FAT32.IFS installed, along with PARTFILT.FLT (since this is how it must be in a FAT32-blind OS/2), all you need to do when you convert FAT16 to FAT32 is to simultaneously convert your OS/2 to become low letter FAT32-aware:

(a) prepare CONFIG.F32 as described previously, including
DaniDASD.DMD instead of OS2DASD.DMD. You've already
got FAT32.IFS and CACHEF32.EXE in your starting version
of CONFIG.SYS, and they should remain.

However REMOVE the PARTFILT.FLT statement you've
currently got. DaniDASD.DMD will give LOW letters to
your FAT32 partitions instead, which is what you want.

(b) copy DaniDASD.DMD to D:\OS2\BOOT

(c) use "new" FDISK (FP10 or newer) to delete and recreate
Boot Manager, used after booting from a modified
utility diskette set that contains DaniDASD.DMD and has
had its config.sys modified to name it instead of
OS2DASD.DMD.

(6) Any time you make FAT32 partitions visible and low lettered, where they weren't visible or were high lettered before, and that sudden FAT32 partition visibility results in an up-shift or down-shift for OS/2 of its boot drive letter from the pre-existing FAT32-blind OS/2 drive letter, you MUST do a reinstall from scratch using my technique.

But if you can perform any one or more actions (e.g. creating or deleting partitions, converting from primary to logical, etc.) to simultaneously bring FAT32 partitions to visibility and yet keep your OS/2 partitions lettered just exactly as they were before, well then you can "cut to the chase" and just install DaniDASD.DMD, FAT32.IFS, and "new" Boot Manager. And you will not need a full reinstall of OS/2.

(7) If you have a working pre-existing multi-OS Boot Manager configuration built according to traditional FAT32-blind procedures, do NOT run FDISK or FDISKPM from FP13 or newer! Repeat: DO NOT RUN FDISK OR FDISKPM from FP13 or newer... unless you are installed as FAT32-aware, per my recipe.

If you do accidentally run the "new" FDISK while still FAT32-blind, this will have the unintended but fatal effect of converting your Boot Manager from FAT32-blind to FAT32-aware, up-shifting your OS/2 boot partition letters on the Boot Manager menu, and making all your OS/2 partitions unbootable. You will receive "OS/2 is unable to operate your hard drive" from each of them.

If this occurs you should boot from the "old" utility diskettes (FP9 or older, or GA install diskettes, or Warp Connect diskettes) and delete/re-create Boot Manager using "old" FDISK. That will put things back to the FAT32-blind way they were originally, and you will once again be able to boot all of your OS/2 systems.

(8) FAT32.IFS can be installed into pre-existing OS/2 systems involving FAT32 in the environment, without requiring a re-install of OS/2. In this case, simply use PARTFILT.FLT to give high letters to the FAT32 partitions and there is no further concern.

The only ABSOLUTELY MANDATORY REQUIREMENT to live with is that you must continue to use the "old" FDISK and the "old" Boot Manager, as they are FAT32-blind.

Repeat: do NOT use the "new" FDISK on a machine which has not had its OS/2 systems installed according to the above FAT32-aware recipe.

(9) If your hard drive is larger than 8G then you need to put Boot Manager at the front of the drive (or at least within the first 8G of the drive). The OS/2 partition(s) also need to fit completely within the first 8G of the drive.

These "minor" requirements may affect how you divide and partition things. For example, you might actually want to put your logical OS/2 partitions near the front of the drive, physically in front of your primary Win98 FAT32 partition, although they are still logical partitions. This would allow you to still define the FAT32 partition as primary, but would permit it to occupy the rest of the large drive as it doesn't have the same <8G consideration.

In other words, you might want the FAT32 partition to be the major partition on the drive, not the OS/2 partitions, and this approach would support that.

Note that OS/2 non-bootable data partitions and FAT32 partitions do not have this same <8G issue as Boot Manager and bootable OS/2. They can actually be anywhere, assuming you've got the IDEDASD driver fix installed and/or that you're using SCSI hard drives. Of course FAT16 partitions cannot be larger than 2G, while HPFS partitions can be of any size.

Epilogue:

Though unproven, it is reasonably felt that the principles stressed in this article should hold up well in any sophisticated environment. In other words, the objective is simply to achieve a FAT32-blind installation of OS/2 to an installable target partition whose letter during the install will remain exactly the same once the installed system is converted to be FAT32-aware. That's exactly what is facilitated through the placeholder partition trick, and in theory this approach should work in any environment.

So even if other operating systems and other partition file types are inserted into the mix, as long as the FAT32-blind drive letter for OS/2 remains the same after becoming FAT32-aware, OS/2 and Boot Manager should work properly no matter how many other drives, partitions, and operating systems are present.

As a specific example of a more complex configuration, I provide my home machine setup which includes four hard drives and nine partitions. Primary FAT32 partitions exist on three drives, and the mix also includes HPFS partitions. It was just recently fully re-installed (both Warp Connect and Warp 4) according to the recipe provided in this article and is working perfectly.

And I now am fully FAT32-aware on that machine, with identical drive letters for FAT32 and FAT16 partitions under both OS/2 and Win98. A dream come true.

As recommended in the article, my two HPFS partitions are placed AFTER the last FAT16/FAT32 partition so as to give them unique high letters for OS/2, and not interfere with the identical low letters assigned to FAT16 and FAT32 partitions for both operating systems.