Windows Drive Letter Changed

Matt · #1 July 10th, 2008, 12:33 AM

Through a series of events that involved accidentally erasing my MBR, not being able to boot, using the Repair Startup on the Vista disk a couple times and then finally being able to boot into Vista, the drive letter of the Windows parition changed from C to D (and my Recovery Partition from D to C). Now, when I boot, I get errors about files not being able to be found and that my account could not be loaded (because the paths are pointing to C).

So, I was wondering if there's anyway to change the drive letter back to C? I tried using diskpart in the Repair CMD line on the Vista disk, but none of the changes "stuck"... Thanks.

kairozamorro · #2 July 10th, 2008, 12:37 AM

Do you have any restore points you could use prior to having to use startup repair? Boot from the disc to do the restore though, as doing so inside of Vista may show none if it points to the C: drive when Vista is considered D:

The next and last workaround I can think of would be to re-install applications giving you problems and verify that the system's variables point to D: rather then C:.

Matt · #3 July 10th, 2008, 12:48 AM

Originally Posted by kairozamorro

Do you have any restore points you could use prior to having to use startup repair? Boot from the disc to do the restore though, as doing so inside of Vista may show none if it points to the C: drive when Vista is considered D:

The next and last workaround I can think of would be to re-install applications giving you problems and verify that the system's variables point to D: rather then C:.

Apparently I don't have any Restore Points... I should, but it doesn't show any (booting from the Vista disc).

That won't work, because most of the functionality in Windows is broken right now, because of the few files it can't load (for example, I can't see anything in the Control Panel).

kairozamorro · #4 July 10th, 2008, 12:51 AM

Well, time to resort to a backup or start backing up important files for a clean install.

Matt · #5 July 10th, 2008, 12:52 AM

I wanted to avoid that...

Terry60 · #6 July 10th, 2008, 02:36 AM

There is a MS registry zap for this exact situation (the only time you should zap the drive letter of the system disk).
Got to go now, so can't look for you, but google for "change system disk drive letter" and look for the MS hits and you should find it easily enough.

btw
Welcome to NST Matt.

Matt · #7 July 10th, 2008, 04:16 AM

Originally Posted by Terry60

There is a MS registry zap for this exact situation (the only time you should zap the drive letter of the system disk).
Got to go now, so can't look for you, but google for "change system disk drive letter" and look for the MS hits and you should find it easily enough.

Thanks, I found the article:

http://support.microsoft.com/kb/223188

Which worked perfectly! Thanks again!

simonb · #8 July 10th, 2008, 05:02 AM

Wow! en francais en plus...

T'es chanceux mon gars...lucky regedit manoeuvre! sweet stuff. I suggest you save files in a restore point also, and a nice registry clean up...software i found for Vista is Registry Mechanic, which is pretty intuitive and user friendly, would most likely fix all glitches and clutches...good job!

Addendum:

Addendum:

Registry Mechanic is more a shareware than a software...Big Mis - Take! (break my thumb in half!)

savage64 · #9 June 15th, 2009, 04:43 AM

Thanks for a great app to facilitate dual boot. I have successfully dual booted XP and Vista on separate HDD's. XP was installed first and then Vista on the second HDD. I have drive letters that change depending on which OS is running and I would like to correct that. I have looked over the MS kb 223188
article and may attempt that method. However, what procedure could I have followed originally to have
prevented the changing drive letters? Is there another way to make the fix other than going into the registry? My experience is limited and hand holding would be appreciated. Thanks.

kairozamorro · #10 June 15th, 2009, 04:52 AM

Hello savage64,

This is perfectly normal behavior. Each individual system may label the drives differently. XP and earlier OSes were really good about being consistent, but for compatibility reaons the latest versions of Windows try to claim C: when possible for older applications that assume the system drive is always C: to work properly.

Now what you can try doing is installing the systems within an installed copy of Windows to partitions you've already defined the lettering for using disk management to your liking, but like I said even if it was I: when the system was installed it could still consider itself C: when you boot into it.

savage64 · #11 June 15th, 2009, 05:18 AM

Thanks, Justin, for your quick response and insight. I may try your work around.

Terry60 · #12 June 15th, 2009, 12:50 PM

Savage, don't use that registry hack.

It's for fixing a system that has got broken (i.e. the letter used to be x:\ and somehow got changed to y:\)
If you use it for cosmetic purposes, because you'd like your system to be a different letter than the one that the OS assigned itself when it installed, you'll break the system.

As well as that registry entry, there will be literally thousands of others which are dependent on what the OS called itself when it installed. That's why the hack's provided, to bring a confused OS back to the way it was at install, so that all the registry entries agree again. If you change it, you'll have thousands of orphan entries unable to find things.

It is completely irrelevant what a different OS calls the partitions. There is no physical link between the partition and the letter, it's just a figment of Window's imagination. Look at the partitions with Linux and there are no letters.

If you want all of your partitions to be the same letters whichever version of Windows is viewing them, then you'll need to install them in a way and a sequence that achieves that result.

There is a downside though.

If you have Windows A installed on C:\ which sees Windows B as D:\ and you install Windows B as D:\ and it can see Windows A as C:\, you will have problems.

Several 3rd party apps, notably Adobe's, which will probably be on all of your OSs, (like Reader and Flash Viewer), have an annoying habit of putting files in C:\Program Files\Common Files even if you instruct them to install to D:\Adobe.

This means that both Windows A and B will have put files in the same place (the second overwriting the first), which will cause unpredictable behaviour at the very least, and might even crash your system.
If you have each booted system considering itself as C:\ and the other systems it can see as notC:\, then you won't get this conflict.

If (like me) your Vista is C:\ and XP is D:\ whichever system is booted, then you'll need to take other measures to prevent C:\ being visible when XP is booted.
Because of the problem of XP destroying Vista restore points, this is necessary anyway, so the Common Files conflict can't arise.

Tell us what you'd like to do, and we'll advise
a) whether it's a good idea
b) how to do it, if it is.