Dualbooting DOS and Vista with (preferably) Vista bootloader


Greetings everyone !

I would like to set up dual booting between Vista and a DOS Ghost client partition [just a FAT12 partition with a couple of tools] - preferably using the Vista bootloader.

I googled quite a bit (wich is what brought me to these very instructive forums!), and this was as close as i could get to my goal. However, it didn't do the trick for me.
I started over a couple of times, but having ntldr, ntdetect.com and a minimalistic boot.ini on my DOS partition didn't work out. The best result i had was Vista Bootloader launching NT loader, in turn launching DOS, just the same as Jedd999 had at some point. (editing boot.ini to have only DOS is what killed my last install :grinning: - i must have done something dumm)

Most of the working solutions included a 3rd party bootloader, but i'd rather avoid that because Symantec Ghost - which i use a lot - is not exactly tolerent of them. :angry:
However, when i decided to give NeoGrub a shot, - because EasyBCD is a great little piece of software ! - i didn't find any documentation concerning DOS :frowning:
I tried a couple of things along the lines of "chainloader /bootsect.dos" but i just kept breaking my system. It's not that i mind breaking systems, but i feel a bit stupid when I can't figure that kind of stuff out.

Any input or tips would be greatly appreciated.
Thanks in advance,
Nedim ~
Hello eviln1 and Welcome to NeoSmart Technologies!

Well i can say that DOS, most likely, isnt supported cause it is no longer used. Even in Windows DOS was taken out with Windows XP and there has been no tractes of actual DOS since Windows 98. That is why DOS was never added to EasyBCD.

You will have to wait for Mahmoud to get back to you as he wrote EasyBCD and will be able to tell you if it is at all possible. :smile:
actually EasyBCD *does* support DOS (the same exact way and steps to support 9x/ME).

It doesn't automate the whole thing, but it does support it.

Nedim, did you manage to create a working bootsect.dos? (I assume so when you talk about the NTLDR booting into DOS working alright)

The minute you have a good bootsect.dos file in the root drive, you can use EasyBCD to add the DOS-based OS entry to the Vista bootloader.
Well i did say that most likely it isnt supported. I didnt say it wasnt for sure as i wasnt positive. :wink:
You know i have read that and i knew that. It just didnt register in my head when i seen this question. I have 1 word with 3 letters for this. DUH! :tongueout:
Thanks for looking into this :smile:

I'm not sure how to tell if my bootsect.dos is at fault.
Here is what the system looks like currently :

[Dos] - 1st primary partition, seen as G:\ by Vista
[Vista] - 2nd primary partition, flagged "bootable"
[Data and stuff] - 3 logical partitions

The [Dos] partition has ntldr, boot.ini, and bootsect.dos present. ntdetect.com as well, but i beleve it is not relevant in this case. The 3 files are attached.

I used EasyBCD (1.7.1) to configure the Vista bootloader, and is currently set as follows :
(two entries for the dos partition are just for testing purposes, obviously. I've tried each of them separately, same results)

There are a total of 3 entries listed in the Vista Bootloader.
Bootloader Timeout: 30 seconds.
Default OS: Microsoft Windows Vista

Entry #1

Name:  Microsoft Windows Vista
BCD ID:  {current}
Drive:  C:\
Bootloader Path:  \Windows\system32\winload.exe
Windows Directory:  \Windows

Entry #2

Name:  Maintenance
BCD ID:  {0b004adf-cb21-11dc-9615-88c0a4df76ee}
Drive:  G:\
Bootloader Path:  \bootsect.dos

Entry #3

Name:  Maint 2
BCD ID:  {0b004ae0-cb21-11dc-9615-88c0a4df76ee}
Drive:  G:\
Bootloader Path:  \NTLDR
Entries #2 and #3 are the attempts to boot with dos. #2 was set up as Win 9x/ME, and #3 as NT.

Neither of them works :|

#2 displays Boot disk failure.#3 reboots the computer straight away.

I'm not sur what am I doing wrong, but i don't mind starting over again and again :smile:

Is there a particular procedure to get a working bootsect.dos ? I got mine from a previous (functional) DOS/XP dual boot.

Thanks again !


  • boot.zip
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No wonder :smile:

Bootsect.dos is specific to the hardware configuration and disk layout of each PC. It is not possible to use the same bootsect.dos across multiple computers; if it were, we definitely host a copy of bootsect.dos the same way we do NTLDR and NTDETECT.COM.

I'll post back in a bit with detailed instructions, my hands are tied right now.
Gah, should have known better :frowning:

I'll start over and be more careful - install dos, install xp, overwrite xp with a vista install. If i manage to make it work, i will post a detailed procedure unless you beat me to it - OR unless yours is much simpler than that.
Oh well.
Vista makes me sad.

This might get a bit off-topic, because it's not only a dualbooting problem. :frowning:

Installing DOS first, and then XP is easy. Dualbooting works just fine.
[DOS] - C:, primary.
[Windows XP] - Logical. Not my fault, XP installation procedure made it that way :s - but i tried both ways.

But, once there is DOS on the first primary partition, no matter what i do - there is no way i can install Vista on the (previously) XP partition. Be it primary, logical, be it formatted through XP, DOS, cfdisk, or the Vista install. Whatever i try i get the "Vista could not find a drive with matching criteria to install" (approximate translation of the french error message).
The Vista CD is Business edition, sold with our DELL computers.

Once the DOS partition is deleted, Vista installs just fine. I haven't been able to find anything specific on the web concerning that particular issue.

I have tried cheating : creating an image of a simple Vista install, and imaging the working XP partition with it. I didn't expect that to work straight away, but i hoped that running the repair boot tools from the Vista install CD could fix that. It didn't. - Vista never booted.
I also tried creating an image of the DOS partition, removing it, but leaving space on the drive for it. Installed Vista without problem, imaged the DOS partition. Vista still worked, but the DOS partition could'nt boot anymore - as expected. :rage:
Last thing i did was try and install Vista through XP - standard upgrade procedure.
But my DOS partition is only 50MB big, and Vista is asking for min. 402 Mo on the C: drive to even start the installation procedure. I've checked the locations of all the temporary folders used by XP, none of them is on C:
So, what's the deal ? There is obviously no easy way to get this done, and none of the sneaky methods I tried has given me any results.

So, maybe booting DOS through NTLDR through VistaBootloader is not the right thing to do, and maybe i have to resort to a 3d party bootloader. But how ? I can't seem to get past the Vista installation procedure in order to have a clean DOS/Vista installation, let alone fixing multibooting.

I would like to make this work out of two reasons. First, at work we use Symantec Ghost (no choice) for deploying OS's and applications, wich we do alot. The 50MB partition contains the Ghost executables and a bunch of other things (hardware diagnostics etc etc.) I do not NEED the DOS partition - since it could be done through network booting - but it makes our lives here MUCH easyer. [especially since creating Ghost network boot images is another hassle with its own set of problems] This being vaguely a Symantec issue i asked them for help, but they weren't able to give any.
Second - it's pureley a geeky ego issue : i don't like giving up. Sure, i want to get the job done, and if the dualbooting DOS and VISTA is not the best way to do it, i will focus on something else. But still, it puzzles me why I can't figure out how to make it work.

Sorry again for disgressing. If anyone has a working method - or even useful hints, i will gladly take them.

Thanks in advance :smile:
Thank you so much Mahmoud !
On a side-note, by starting from scratch i noticed a mistake i was making (and wich curiously allowed me to get past the DOS/Vista installation issue) :
Symantec Ghost has a wizard to create an image of the bootable partition. If that image is untouched (as in not modified by the symantec image editor AT ALL), it becomes, well, unbootable. It is juste an image of a FAT12 partition with some files in it.
When I did try with an altered ( = unbootable) image, i could install Vista right after DOS, with no errors whatsoever during the installation process.
When i started again with a actually bootable DOS partition, that's where Vista started complaining.

I don't have any proper DOS disks lying around to try an old school floppy disk installation - i actually never needed any. I'm curious to see if the issue is related only to Symantec's installation method, or is it inherent to Vista...
Nedim, I've found a way to code the DOS support differently to make it massively easier to dual-boot.

I'm working on the documentation now, and you'll have to use a heavily worked-around method to get it to work until I publish a new version of EasyBCD (this'll probably have to wait for EasyBCD 2.0)
Hello eviln1 and Mahmoud,

Do you have the mentioned workaround instructions for this? It might help me with my DOS/Vista dual boot.