Changing the System Drive letter in Windows XP

[Dave]

I have a colleague who has a requirement to change the
system drive of his Windows XP Pro installation. The
reason for this is that after a motherboard failure he has
found after re-installation that for somereason the system
has shoved what was a C Drive to an F drive, the
replacement motherboard is the same as the one that has
failed, I should add. So currently his machine is booting
from drive F when it should be booting from drive C. There
is nothing present in the machine that is using the drive
C assignment. So the question is can the F drive be re-
assigned to C? It can't be done in Disk Manager, he's
already tried.

 

[R. C. White]

Hi, Dave.

For an explanation of why it happened, see this KB article:
Drive Letters Change Unexpectedly When You Install Windows XP
http://support.microsoft.com/?kbid=326683#appliesto

That article points you to another:
HOW TO: Change Drive Letter Assignments in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;EN-US;307844

However, as 307844 says, "Changing the drive letter of the system volume or
the boot volume is not inherent to Disk Management."

So, your colleague may have to choose between just "living with" Drive F: as
the system partition, or reinstalling WinXP. He could do an "in-place
upgrade", as described in:
How to Perform an In-Place Upgrade (Reinstallation) of Windows XP
http://support.microsoft.com/default.aspx?scid=KB;en-us;q315341

But note that this is not intended as a time-saver for installing WinXP
itself, although it should preserve installed applications and data - and
most of his tweaks. And he will need to go to Windows Update as soon as he
gets his firewall and antivirus working again and gets back online to be
sure he has SP1 (unless it's included on his WinXP CD-ROM) and all the later
security fixes. Better plan on half a day for the entire reinstallation.

Be sure that no other Active (bootable) partition is on any HD plugged in
when running WinXP Setup. Unplug all drives except the primary master HD
and the CD drive that will be booting the WinXP CD-ROM. After WinXP is
installed (and C: is the system partition), shut down, reinstall the other
drives, reboot into WinXP and use Disk Management to assign the other drive
letters.

Let us know if you find a shortcut.

RC

 

[Alex Nichol]

I have a colleague who has a requirement to change the
system drive of his Windows XP Pro installation. The
reason for this is that after a motherboard failure he has
found after re-installation that for somereason the system
has shoved what was a C Drive to an F drive, the
replacement motherboard is the same as the one that has
failed, I should add. So currently his machine is booting
from drive F when it should be booting from drive C. There
is nothing present in the machine that is using the drive
C assignment. So the question is can the F drive be re-
assigned to C?

Two things - one the partition becoming F is commonly the result of
having a Zip drive present at the time of running setup

Second: If this was a reformat and clean reinstall (which for that to
happen I think it will have been) then the new letter will be pervasive
in the registry. The only practicable course is to start over and ,
reinstall, including deleting the partition and making a new one,
*without* the Zip drive being present until setup is complete.

If it is a case where the letter 'just changed', without a new setup,
then the registry will be all references to C still, and you can do it
manually with regedit - at
HKEY_LOCAL_MACHINE\System\Mounted devices look in the right pane for the
line
DosDevices\F:
and double click it. Very carefully change F to C, then close and
reboot.