Help Re: Drive Letter Assignments for Boot Drive/Partition

Donald S

I have a question about drive letters assigned to the current boot drive.

I am running Win7 on one drive, and WinXP on another. The Win7 drive has the Win7 partition, and also has a "system reserved" partition for troubleshooting. That partition currently has no drive letter.

When I boot into Win7, the assigned drive letters are Windows 7 (C:smile: (System, Boot); DVD (D:smile:; and WinXP (E:smile:;

When I boot into WinXP, the assigned drive letters are WinXP (D:smile: (Boot); Windows 7 (System) (E:smile:; and DVD (F:smile:

My problem is with the drive letter assigned to the WinXP drive when I have booted into that operating system. Some software requires a C: drive to be present, large enough to accomodate setup files. Consequently, I sometimes have installation issues with some software. The "System Reserved" partition will take a C: drive letter (which was originally what EasyBCD gave it when I set up the dual boot), but when that is the case, it's partition is too small to accommodate setup files, and I don't want to change that partition.

Is there a way I can set things up so that the current operating system (boot) drive always has the letter C: assigned?

Only by pre-planning at install time.
Generally speaking, Windows (any flavour) will install as C: if you install it by booting the CD/DVD and It cannot see another Windows.
Once it has installed, whatever letter it used is set in stone unless you get a 3rd party app capable of altering the thousands of registry entries which reference it.
There is no problem running XP as D (mine is), as long as it cannot see another Windows which is C:
Adobe notably will put stuff in C:\Program Files\Common Files if it finds one, even when you've told it to install in D:\Myapps. This will obviously clash with the same files installed on the "real" C: with unpredictable results for both OSs.
You should not let XP see Windows Vista or Seven. It will corrupt their restore points.
Use this hack
You should not let XP see Windows Vista or Seven. It will corrupt their restore points.

Well, my WinXP as D: can see my Win7 as E:

Are corrupted restore points the only problem here, in addition to application install problems? (I can probably live without restore points)

And, do you know of an app than can change all the XP D: references to C: ? (I seem to remember the old Parition Magic software having a utility such as this...)
Brave man !
No restore points means no way back if a WUD goes wrong (or is interrupted).
SR has saved my bacon more times than I can remember, but if you're happy to reinstall W7 and all your apps at the drop of a hat, and all your user data is regularly mirrored to external storage ????

I don't have any personal experience of such an app (don't actually know that one exists, but in theory it's possible)
What is C: when XP is booted ?
Windows doesn't skip letters.
Unless you've manually assigned letters, WIndows always assigns them alphabetically in sequence.
Probably your fastest resolution would be to reinstall XP with the other HDD disconnected. It will be C: then.
If you blanch at the thought of doing all that again, perhaps you'd better reconsider your attitude to SR ?
Brave man !
No restore points means no way back if a WUD goes wrong (or is interrupted).

I've had mixed success with system restore. Recently I used it to recover an uninstalled program. Windows claimed it was successful, but the application kept crashing. I keep my documents safe. And while it's not everyone's "cup of tea", I don't mind reinstalling my operating systems once in a while. After a point, the only way to have a "clean" operating system is to do a "clean install" :smile: Besides, a lot of the extras I install are not much worth keeping!

What is C: when XP is booted ?
Windows doesn't skip letters.

When XP is booted, C: is the "system reserved" partition. That's how EasyBCD set it up, even though when I boot into Win7, it is invisible (i.e. it has no drive letter.) Of late I have removed the C: drive letter from the "system reserved" partition when I'm booted in WinXP, otherwise some applications try to write to it. And when it's invisible in WinXP, rebooting doesn't produce a C: drive.

Just to be clear, when WinXP is booted, and Win7 is listed as E: drive, is corruption of system restore files still a problem?

And thanks, btw, for you interest and quick replies.
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Yes, SR points get wiped no matter what letters are involved.
The problem is that SR changed design with Vista to use the Volume Shadow Copy service (which is also responsible for backup/restore), but continued to use the same name for the restore folder (super- hidden) which XP used.
XP sees the folder(s) on all the Vista/7 drives which are being monitored by SR, says "they're not right !!" and proceeds to "fix" them back to XP format.
Next time Vista/7 runs it has to reinitialize the folder and every restore point, and all backups are lost.

Why on earth they didn't just make the Vista folder a slightly different name, so that XP ignored it, I cannot fathom, but who can guess what goes on in the minds of the Windows design team(s) ?
I imagine it's one of those "slipped through the cracks" unintended consequences of a massive modular design process spread across such a vast organization.