Change drive letter for system drive

I installed a new internal hard drive to replace my old SATA drive C. After
installing the new SATA drive and installing Windows XP I discovered that
the drive was assigned the letter "I".

Disk management will not let me change the letter because it is a "system
volume". I notice that C is not assigned to any other drive.

I guess I can live with the drive being labeled "I" unless it is going to
cause problems installing programs. How can I change it?

You will have to live with it or you will have to reinstall Windows.

You can't, at least not short of reinstalling Windows. You can change
the letter of any other drive, but not that one.

Keeping it as I: doesn't really matter. There's no particular reason
why it needs to be C:. Mine is F: (for reasons I won't bother
explaining), and I have never had a problem resulting from that
unusual name.

While it's not crucial that your system (boot) drive be designated as the C:
drive and in theory you can live with your system (boot) drive being
designated as an other-than-C: drive, our experience in a Windows
environment over the years tells us that for a variety of reasons it *is*
most desirable for your system (boot) drive to have the C: letter
designation.

As you have discovered you cannot use XP's disk management utility to change
your system (boot) drive from I: to C:. While there have been some published
hacks indicating that registry modifications can achieve this change, we
have never found these changes reliable.

So my advice would be that if it's practical for you to do so, "bite the
bullet" and perform a fresh install of the XP OS. As I'm sure you recognize,
should you do this, all your previously installed programs will need to be
subsequently reinstalled. So you will have to decide whether a fresh install
is practical under your present circumstances. From your description of
events it doesn't seem that you've installed too many programs & other data
on your new HDD so I'm assuming it won't be too onerous a chore for you to
simply undertake a fresh-install of the XP OS.

Again, if practical, I would strongly advise you go that route. For safety's
sake (so that you don't run into the same problem again) it would be best if
you would disconnect all other HDDs and storage devices from your system,
especially another bootable HDD.

That might have been true for Windows 9x operating systems but for NT
operating systems this is really a non-issue. The only time this is a
problem is when trying to install older DOS or early Windows
applications that insist on being installed on a C: drive, otherwise
having an NT operating system on a drive other than C: is not a problem.

That's not been my experience at all. Please tell us what you think
that "variety of reasons" is.

Time & time again over the years we have consistently run into user problems
because the user's boot (system) volume had not been assigned the C: drive
letter. In most cases the situation originally arose because of user error
when installing the Windows OS, e.g., other bootable storage devices were
present at the time of the OS installation or a glitch in the disk-cloning
process resulting in the cloned HDD receiving an other than C: drive letter
assignment.

In any event, the problems we (or, more precisely, the user) subsequently
encountered because of this situation involved the inability (present &
future) for the user to install a particular program on his/her system
(boot) drive because the program simply balked at any attempt to install
such program other than on a C:
designated drive. While it is true that virtually every major program in
existence today will allow this capability, there are still a host of
programs out there (including "custom-made" programs) that simply don't have
this capability. They are programmed to permit installation *only* on a
drive designated as C:. Whether these types of programs can be considered
poorly designed/programmed is beside the point. They are out there in
considerable numbers and users use them.

We also encountered a fair number of problems where future user
configuration modifications simply wouldn't work because the program had
originally been installed on a non-C: designated drive.

Also, we've run into many problems with subsequent upgrades, patches, fixes
of one sort or another affecting an installed program that either would not
modify the targeted program because the program resided on an other-than-C:
drive (even though the user had not originally experienced any difficulty in
installing that program on a non-C: drive), or even if the upgrade, patch,
etc. appeared to be installed properly we ran into subsequent problems of
one kind or another which we attributed to the fact that the program resided
on a non-C: designated drive.

So all-in-all as I've suggested to the OP, if it's not too terribly onerous
to "start over" as it were and perform a correct fresh install of the XP OS
so as to install that OS on a C: designated drive, our advice is do so. On
the other hand if it's simply impractical for the user to do this because
the programs/applications installed on drive make it too difficult or
impossible for the user to reinstall these programs/applications following a
fresh install of the OS (together with the usually onerous chore of
reinstalling all the MS critical updates), then he or she can live with the
present situation and hope for the best.

I am going to leave the drive with
"I' designated until Windows 7 becomes available. I am leary that a
reinstall of XP would correct the issue.

[gachiman]

Switching your system volume from any other letter to C is doable. It's definately not for the feint of heart and you could easily destroy your installation if you are not careful. It probably is better in the long run to backup all your data and reinstall windows and reinstall all of your additional software.

You can change the drive letter in windows xp with administrator rights in the registry. Most of the critical windows functions boot from device ID rather than drive letter. The device ID will stay the same no matter what letter your drive is named. Windows should boot up in a very limited state, but be aware that 99% of all the software installed will not be accesable as well as a lot of windows functions immediately after reassigning the letter. The big problem you face is to do a sweeping change of thousands of entries in your registry to point to the newly assigned drive letter. There are free utilities out there to do this (windows does not provide a search and replace for your registry), although I don't remember exactly which one I used when I was in a similar situation to you. Try Googling Windows xp registry search and replace. You will need to download one or more of these programs to your desktop before you do anything since you will not have internet access after you switch drive letters and explorer will most likely crash your system trying to browse anywhere other than your desktop. Do not install any of these programs before you reassign drive letter either or they will most likely not run.

Once you have a registry search and replace application downloaded to your desktop, log into windows as an adminstrator.

go to start > run
type in regedit, then hit enter

Browse to registry key HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices

Look in the right panel and you'll see entries like \DosDevices\I:

find the one associated with your current system volume, then right-click it and rename it to \DosDevices\C:

If there is already an entry for \DosDevices\C: you'll need to rename it to an unused letter first. If it's just a removable drive, then it's really not a big issue.

close regedit and reboot your machine.

If all goes well you will get back your desktop after reboot. You'll probably get a lot of error messages. Don't worry about those right now, just close all warnings.

You should now install one of the utilities that you downloaded to your desktop to find and replace registry entries. then launch the program after installation

do a search for I:\ and replace all with C:\ (provided I:\ was your old system volume letter). Once it has completed, reboot your machine again. You should have a very stable version of windows with 99% of all your applications and windows utilities running. A few applications will probably prompt you with a grey box looking for a particular file. If you look at the beginning of the string you will see it is probably looking for it in I:\path\to\wherever\the\file\is\installed Simply change the I to C and leave the rest of the path intact and tell it OK. It should find what it was looking for an resume to run as intended.