Dual boot drive designation

[M$]

Is there a way to force XP Pro to assign C: to the local partition where it
resides in a dual boot with another XP pro. By that I mean that when I boot
from partition 1, XP will designate partition one as C: drive and partition
2 as D: drive. When I boot from partition 2, it will become C: drive and
partition 1 D: drive.

I have one PC, Dell 4600, where the dual boots work that way, but I'm
setting up a second PC that I built, and it does not do that.

Any ideas on how I can force XP to do that?

I tried to renaming the drive letters in Disk management but it wont let me
reassign a letter to a boot partition.

 

[Pegasus \(MVP\)]

Is there a way to force XP Pro to assign C: to the local partition where it
resides in a dual boot with another XP pro. By that I mean that when I boot
from partition 1, XP will designate partition one as C: drive and partition
2 as D: drive. When I boot from partition 2, it will become C: drive and
partition 1 D: drive.

I have one PC, Dell 4600, where the dual boots work that way, but I'm
setting up a second PC that I built, and it does not do that.

Any ideas on how I can force XP to do that?

I tried to renaming the drive letters in Disk management but it wont let me
reassign a letter to a boot partition.

You would have to use a third-party boot manager with disk-swapping
capabilities to do this. XOSL can do it - it's free too!

 

[M$]

Thanks for the reply.

As I mentioned in my original post, I did it on a Dell Dimension 4600
without the use of any disk mangers or any other utility other then the ones
I'm going to mention in here. The problem is, when I did it, I did not care
at that time about drive letter assignments, and therefore, I'm not sure
what exactly or what step in the procedure that I used caused the drive to
be C: regardless to which partition I boot from.

This came all about by accident so to speak. Several months back, I
installed Win98se to this PC which had XP pro already installed from
factory. All dells are configured with 2 partitions by default. One small
partition, 32 Meg approximately, which is FAT and then the NTFS partition
which has XP on it. The 32 meg partition is hidden and is used for
recover/diagnostic purposes. It has no drive letter assigned to it, at least
not when booted into XP, but it can be seen by the disk manager in XP.

I used Mandrake Linux to resize the NTFS portion to make room for a FAT32
partition where I installed Win98. After Win98 was installed, I had to do an
In-place install of XP in order to get XP to boot again since Win98 had
changed the MBR from what I understand. A while later, I decided that Win98
was of no use any longer, so I booted from the XP CD and formatted the Win98
partition to NTFS and installed XP. That is how I ended up with a XP dual
boot where the C: drive is always assigned to the partition that the OS
booted from.

From what I've been able to determine so far it would seam that either the
Hidden partition, using Linux to resize the XP partition, or installing
Win98 is what did it. I was just wandering if any one else knew exactly what
procedure would cause this behavior?

According to Microsoft the dive letters are assigned based on the system
partition that the OS uses when booting, location of the boot loader. I
don't have access to that PC now, but I will take a closer look ASAP at each
of the partitions and see what files, like NTLDR, etc. are on each partition
and maybe that will give me a clue. Also, which partition is active may have
something to do with this.

Thanks.

 

[M$]

Ok, I was able to duplicate this phenomena. I successfully created a dual
boot setup of XP Pro (one copy of XP on partition 1 & another on partition
2) where each copy of XP resides on C: drive when booted. This same method
should also work for dual boots of XP & W2K where both OSs will think they
live on C: drive.

This is how I got there:

1. Install XP on a clean HD (I used the whole HD and a single partition to
start with)

2. Boot with Mandrake Linux CD and resized the NTFS partition (this could
have been done right away in step 1 using XP unless you already have an OS
installed and want to preserve it). Don't install Linux, just use it or any
other partitioning sw to resize the partition, and then exit.

3. Used this guide to install Win98
http://www.winxpfix.com/page5.htm#howwin982000 Note: I had to use (setup /p
i) switch to get Win98 to run on my HW (Dell Dim4600).

4. Once the XP/Win98 dual boot was complete, I booted again from my XP cd,
and installed XP on the Win98 partition. I reformatted the partition to NTFS
during the install.

5. . and that is it! No matter which partition you boot from, it will always
be referenced as C: drive.

I'm not exactly sure how this phenomena is triggered, but I think it has
something to do with the part where I used FDISK to activate the new
partition. I'm not sure that installing Win98 is necessary - there may be a
shortcut to creating this phenomena. The reason that I think the install of
Win98 could be skipped is that when I installed XP to the second partition,
I formatted the partition, FAT32, to NTFS. This effectively wiped out Win98.
Therefore, the trick must lie with FDISK?

Maybe, there is some one out there that has a better understanding of how
partitions, etc. work and could explain how this happens and likely come up
with a much shorter and simpler procedure for doing this.

If you know what is happening here, please let me know, I'm very interested
in understanding how exactly this works.

Thanks.

 

[Pegasus \(MVP\)]

This is an interesting method of multibooting, one that I was not
aware of before. Here is what happens:

- The first partition is an NTFS partition. It contains Win2000 or WinXP.
- The second partition is a FAT32 partition. It is set to "active". It
contains the following:
- The Win2000 boot sector (which means that the boot process
invokes the file c:\ntldr located on this partition).
- The file c:\ntldr (which processes c:\boot.ini, containing the
OS selection menu).
- The file c:\ntdetect.com (which launches Win2000).
- The file c:\bootsect.dos (which passes control to the Win98 boot files)
- The Win98 boot files c:\io.sys, c:\msdos.sys, c:\command.com
- When you select Win2000 during the boot process then ntldr
passes control to the Win2000 system files on the FIRST partition.
Since it's the first partition, it acquires drive letter C:. The FAT32
partition will now appear as drive D:.
- When you select Win98 during the boot process then c:\bootsect.dos
passes control to c:\io.sys etc. The NTFS partition will remain
invisible,
because Win98 cannot see NTFS partitions.

And here is an alternative way to implement this solution, in steps
that show what actually happens.
1. Start off with a system where Win2000/XP is installed in the
first NTFS partition.
2. Copy the hidden files c:\boot.ini, c:\ntldr and c:\ntdetect.com to a
floppy disk.
3. Use a suitable tool to create a primary FAT32 partition. Format it.
4. Use a suitable tool to make this partition active.
5. Install Win98 in this partition.
6. Boot into a DOS prompt (press F8 during the early boot phase).
7. Copy the files made in Step 2 to c:\.
8. Get a copy of bootpart.exe from here:
http://ourworld.compuserve.com/homepages/gvollant/bootpart.htm
9. Run these commands:
bootpart winnt boot:c:
This will create the Win2000 boot sector on the FAT32 partition.
bootpart win95 c:\bootsect.dos "Windows 98"
This will create the Windows 98 boot sector file. It will also create
a Windows 98 entry in c:\boot.ini

What you observe here is not really a phenomenon (singular: phenomenon,
plural: phenomena) but is entirely whithin the scope of the Windows
boot process. I'm not sure if Ole Martin Rockstad was the first to think
of it but it's certainly an elegant method of booting into Win98 on a
system where Win2000/XP is already installed in an NTFS partition.

 

[M$]

After I made this post, I got thinking and realized what was happening.
Steps 2 & 3 are not needed to get this effect. Here is the simple and
revised proceedure.
1. Start with a clean/new HD
2. Boot XP from CD
3. Create a partition sized to your liking and leave the rest of the disk
space unpartitioned/free space.
4. Install XP on portion 1
5. Boot PC using a Win98 CD or floppy
6. Run FDISK and create a Primary DOS partition from the remaining space on
the HD & make it active.
7. Boot from XP CD
8. Install XP on the newly created partition 2 & format it to NTFS
9. Edit Boot.ini to include partition 1 as one of your boot options.
10. Your done!

Note: Before you install the second copy of XP, change the drive letter of
your CD drive while booted into XP on partition 1 from D to E. This way,
when you are done with the dual boot, the second partition in will be
assigned D drive while booted into partition 1. This is just a cosmetic
thing.

Also, you can now make any of these two partitions active and it will boot
since either of the partitions can act as the system partition. Just
remember to edit boot.ini on the correct partition to when changing the
active partition.

 

[Jetro]

Simply create two, three, four primary partitions and reassign the Active
flag before every setup. Edit final boot.ini file.