Take a look at our
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message

W7 shifts Drive Letters

Windows 7 on ThinkPads
Post Reply
Message
Author
RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 21824
Joined: Mon Sep 18, 2006 5:17 am
Location: Wexford, Éire
Contact:

W7 shifts Drive Letters

#1 Post by RealBlackStuff » Fri Oct 16, 2009 3:29 pm

Before I installed W7 RC on my desktop PC I had the following drives:
C: Windows XP (secondary installation)
D: Programs
E: Data
F: Empty for W7
G: Windows XP (primary installation)

I then decided to install W7 RC Ultimate 32-bit. During install it asked Upgrade or Custom Install.
I chose Custom Install, and selected the (empty) F-drive for W7.

After installation I have the following situation, when in W7:
C: Windows 7
D: Windows XP (secondary installation)
E: Programs
F: Data
G: Windows XP (primary installation)

But when I go back in my 'old' Windows XP (primary on G) I see this again:
C: Windows XP (secondary installation)
D: Programs
E: Data
F: Windows 7
G: Windows XP (primary installation)

Please note the crazy shift in drive letters!
Anybody else have/had this problem?
Still NOT a great day for a Guinness! (the Real Black Stuff).
Ireland is on FULL lockdown until Easter 2021!
Covid-19: Stay safe, so Mask it or Casket!

K0LO
Senior Member
Senior Member
Posts: 659
Joined: Wed Sep 07, 2005 12:14 pm
Location: State College, PA, USA

Re: W7 shifts Drive Letters

#2 Post by K0LO » Fri Oct 16, 2009 8:11 pm

RBS:

That's normal. On first boot, any Windows OS will assign drive letters according to a predetermined heirarchy. It usually goes something like this (I may not paraphrase this exactly correct): Booting OS gets C:, first logical partition gets D:, next primary partition gets E:, etc. Thereafter, these assignments are stored in the registry of the applicable OS and will persist upon future boots.

If you don't like the drive letters assigned by default you can change them using Windows 7 Disk Management console. You won't be able to change the current OS partition's drive letter (C:) but you should be able to change the others.

Windows 7 will always see its own partition as C: when you are booted to Win7, and Windows XP will always see its own partition as C: when you are booted to XP. The others are arbitrary. You can change them to suit your preferences.
Mark

X61T 7764-CTO, Core 2 Duo L7500 LV 1.6 GHz, 4 GB RAM, 120 GB Intel X25M SSD
Multiboot w/Grub4DOS -- Windows 10, MustangPE, PartedMagic
My ex: X41T (2005 - 2009)

Marin85
Senior ThinkPadder
Senior ThinkPadder
Posts: 2975
Joined: Sat May 12, 2007 10:54 am
Location: Munich, Germany

Re: W7 shifts Drive Letters

#3 Post by Marin85 » Fri Oct 16, 2009 10:55 pm

I have the exact same observation on my dual-boot setup (adding an external HDD plus an ultrabay HDD). I´m not worried about that at all, but I´m worried about how to permanently assign a given letter to my external HDD. So far I have tried both Acronis Disk Director and Windows Disk Management console, but upon second or third reboot the drive letters of all my secondary physical and virtual drives, including the external one, are messed up again. If I haden´t my music library on my external HDD, that wouldn´t be a problem. Now, every now and then I have to manually add the library, not to mention that some of the playlists turned out to be drive-letter-sensitive. I figured I could assign something like the letter X to the external HDD, so there would be no conflict/reason for the other devices to steal it as it appears to be far enough, I figured wrong... But at least it lasted longer than any other *solution*. Perfect would be if there is some way to make non-OS partitions being treated by any windows installation with one and the same letter every time the device is mounted. Like putting some file on every partition in question that would indicate the desirable letter and would be automatically read by windows? This way the drive letter shift will be avoided for non-OS partitions. The only issue would be what happens if the non-OS partition letters are already fixed and the user decides to go multi-boot...

PS: Sorry if this is kind of hijacking the thread, thought it might be considered related :)
IBM Lenovo Z61p | 15.4'' WUXGA | Intel Core 2 Duo T7400 2x 2.16GHz | 4 GB Kingston HyperX | Hitachi 7K500 500 GB + WD 1TB (USB) | ATI Mobility FireGL V5200 | ThinkPad Atheros a/b/g | Analog Devices AD1981HD | Win 7 x86 + ArchLinux 2009.08 x64 (number crunching)

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 21824
Joined: Mon Sep 18, 2006 5:17 am
Location: Wexford, Éire
Contact:

Re: W7 shifts Drive Letters

#4 Post by RealBlackStuff » Sat Oct 17, 2009 6:08 am

Thanks guys, for this information.
What a colossal piece of crap!
If I wanted W7 on my C-drive, I would have installed it there!
I guess the same happens with W7 RTM (and presumably W7 Retail after Oct. 22)?

I have a few more questions before I waste my time on W7.
I get "Access denied" on W7 "Documents and Settings" when I am in XP, why?
I want XP as default boot-OS, instead of W7. How do I change this?
How do I UNinstall this W7?
Still NOT a great day for a Guinness! (the Real Black Stuff).
Ireland is on FULL lockdown until Easter 2021!
Covid-19: Stay safe, so Mask it or Casket!

K0LO
Senior Member
Senior Member
Posts: 659
Joined: Wed Sep 07, 2005 12:14 pm
Location: State College, PA, USA

Re: W7 shifts Drive Letters

#5 Post by K0LO » Sat Oct 17, 2009 8:04 am

RBS:

It is a common misconception that drive letters in a Windows operating system are absolute. They are not. A drive letter is only meaningful to the currently-running operating system. For example, if you have XP and Win7 both installed then each operating system keeps its own independent list of drive letter assignments. The designator C: does not refer to an absolute partition location; only to a location that has meaning to the OS that is currently running.

Second, assignment of drive letter C: to the OS system partition is not a Windows 7 issue. All Microsoft operating systems will assign the drive letter C: to their system partitions by default. XP and earlier would allow assignment of a different drive letter if it was the second instance installed on the disk, but the newer operating systems (Vista and Windows 7) have a strong preference to assign themselves the C: designator.

A third point is that I am not a big fan of multibooting "The Microsoft Way", where each OS is visible to the other installations on the disk. For one thing, you get entangled boot files that make it difficult to remove one or more of the installations later. On your current system, one of the partitions (the one that is currently Active) contains all of the boot files for all three operating systems. They're probably on the XP partition, but you can find out by using Disk Management console to determine the active partition. The last OS installed (Windows 7 in your case) would have taken over responsibility for managing the boot process for all three. So removing Windows 7 now becomes more complicated than it needs to be.

This is why I prefer using third-party boot managers so that when you run OS #1, the other installations are hidden from each other and thus are completely independent of each other. I only bring this up because you will eventually run into an issue with Windows that hasn't bitten you yet, but it will. With the way that you have your multiboot setup configured, each time that you run one of the XP operating systems it will destroy all of the restore points on any Vista or Windows 7 installations visible to XP. This is another reason for keeping the operating systems hidden from each other.

None of this answers your questions, but I wanted to provide some background before you conclude that this behavior is unique to Windows 7.
Mark

X61T 7764-CTO, Core 2 Duo L7500 LV 1.6 GHz, 4 GB RAM, 120 GB Intel X25M SSD
Multiboot w/Grub4DOS -- Windows 10, MustangPE, PartedMagic
My ex: X41T (2005 - 2009)

K0LO
Senior Member
Senior Member
Posts: 659
Joined: Wed Sep 07, 2005 12:14 pm
Location: State College, PA, USA

Re: W7 shifts Drive Letters

#6 Post by K0LO » Sat Oct 17, 2009 8:18 am

RealBlackStuff wrote:...I have a few more questions before I waste my time on W7.
I want XP as default boot-OS, instead of W7. How do I change this?
This should be the easiest question to answer, but to be absolutely sure of the syntax could you post the output of the following command? In Windows 7, click on Start, type "cmd". The first search result should be "cmd.exe". Right-click on cmd.exe and choose "Run as administrator" to bring up an elevated command prompt. Enter the following:

Code: Select all

bcdedit
Copy and paste the output here.

The command to make XP the default boot-OS should be:

Code: Select all

bcdedit /default {ntldr}
However, I want to see your current BCD contents to be sure since you have two XP installations on your system.
Mark

X61T 7764-CTO, Core 2 Duo L7500 LV 1.6 GHz, 4 GB RAM, 120 GB Intel X25M SSD
Multiboot w/Grub4DOS -- Windows 10, MustangPE, PartedMagic
My ex: X41T (2005 - 2009)

K0LO
Senior Member
Senior Member
Posts: 659
Joined: Wed Sep 07, 2005 12:14 pm
Location: State College, PA, USA

Re: W7 shifts Drive Letters

#7 Post by K0LO » Sat Oct 17, 2009 8:36 am

RBS:

My apologies for the former post about bcdedit. I'm too much of a command-line guy and forgot that there is a simpler way to do this from the GUI.

Click on START, type "advanced system" and the first search hit should be "View advanced system settings". Click on the "Settings" button under "Startup and Recovery". Under "System startup" select the default OS from the drop-down list.
Mark

X61T 7764-CTO, Core 2 Duo L7500 LV 1.6 GHz, 4 GB RAM, 120 GB Intel X25M SSD
Multiboot w/Grub4DOS -- Windows 10, MustangPE, PartedMagic
My ex: X41T (2005 - 2009)

Marin85
Senior ThinkPadder
Senior ThinkPadder
Posts: 2975
Joined: Sat May 12, 2007 10:54 am
Location: Munich, Germany

Re: W7 shifts Drive Letters

#8 Post by Marin85 » Sat Oct 17, 2009 11:29 am

RealBlackStuff wrote:I get "Access denied" on W7 "Documents and Settings" when I am in XP, why?
I want XP as default boot-OS, instead of W7. How do I change this?
How do I UNinstall this W7?
If you mean C:\Documents and Settings, you will get *Access Denied* on it even from within Windows 7, because actually there isn´t such folder. It´s one of the many junction points in Windows 7 that are supposedly there to maintain compatibility with older stuff. All these fake folders are hidden and protected by the OS, this means you will have to check/uncheck the corresponding folder and search options to make them visible under Windows 7.
Last edited by Marin85 on Sat Oct 17, 2009 2:53 pm, edited 1 time in total.
IBM Lenovo Z61p | 15.4'' WUXGA | Intel Core 2 Duo T7400 2x 2.16GHz | 4 GB Kingston HyperX | Hitachi 7K500 500 GB + WD 1TB (USB) | ATI Mobility FireGL V5200 | ThinkPad Atheros a/b/g | Analog Devices AD1981HD | Win 7 x86 + ArchLinux 2009.08 x64 (number crunching)

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 21824
Joined: Mon Sep 18, 2006 5:17 am
Location: Wexford, Éire
Contact:

Re: W7 shifts Drive Letters

#9 Post by RealBlackStuff » Sat Oct 17, 2009 1:40 pm

Even more BS.
It is MY PC and I should have full access to MY installation!
I'm not sure if I'm going to like W7 if it doesn't behave better. :BAAAD!:

And the Drive-letter shift is the worst case of bad behavior I have seen in many years!
If W7 wants to be on the C-drive (while installed on the F-drive), it should have ONLY swapped C and F.
Bad start :evil: :evil:

I won't play with W7 until next week..., so I'll just sit at my PC during boot to select my OS.
Still NOT a great day for a Guinness! (the Real Black Stuff).
Ireland is on FULL lockdown until Easter 2021!
Covid-19: Stay safe, so Mask it or Casket!

Marin85
Senior ThinkPadder
Senior ThinkPadder
Posts: 2975
Joined: Sat May 12, 2007 10:54 am
Location: Munich, Germany

Re: W7 shifts Drive Letters

#10 Post by Marin85 » Sat Oct 17, 2009 2:59 pm

I don´t fully understand your considerations. You do have full access to your installation. It is just that many things work differently than they did under XP or Vista. But I agree the drive letter shift is somewhat dumb side effect and can be quite annoying.
IBM Lenovo Z61p | 15.4'' WUXGA | Intel Core 2 Duo T7400 2x 2.16GHz | 4 GB Kingston HyperX | Hitachi 7K500 500 GB + WD 1TB (USB) | ATI Mobility FireGL V5200 | ThinkPad Atheros a/b/g | Analog Devices AD1981HD | Win 7 x86 + ArchLinux 2009.08 x64 (number crunching)

qviri
ThinkPadder
ThinkPadder
Posts: 1275
Joined: Sat Nov 25, 2006 5:45 pm
Location: Berlin, Germany

Re: W7 shifts Drive Letters

#11 Post by qviri » Sat Oct 17, 2009 3:16 pm

RealBlackStuff wrote:What a colossal piece of crap!
How do I UNinstall this W7?
Boot into XP and remove (or format) this W7 partition (what you know as the "drive"). You may have to redo the XP boot manager to get rid of this W7 entry.
X220/IPS, T60p/IPS
Nothing endures but change

K0LO
Senior Member
Senior Member
Posts: 659
Joined: Wed Sep 07, 2005 12:14 pm
Location: State College, PA, USA

Re: W7 shifts Drive Letters

#12 Post by K0LO » Sat Oct 17, 2009 3:56 pm

qviri wrote:Boot into XP and remove (or format) this W7 partition (what you know as the "drive"). You may have to redo the XP boot manager to get rid of this W7 entry.
Not quite. Booting is now managed by W7 boot manager, not XP boot manager. The boot manager is currently installed on the active partition; not the W7 partition. Even though you have deleted the W7 partition, the boot files and boot manager from W7 are still in use. From here you have two choices:

1. Continue to use the W7 boot manager but delete the Windows 7 entry from the list. This is done with the W7 bcdedit command, so if you've already deleted the W7 partition then you'll have to edit the BCD from the W7 install disk's recovery environment. If you're planning ahead you can make the change from within W7 before nuking the partition.
2. To delete the W7 boot manager and return to using ntldr as the boot manager you should boot to the Windows XP recovery environment from a WinXP CD and change the partition boot record so that it boots XP-style (from ntldr) instead of Vista/Win7 style (from bootmgr). Do this with the fixboot command. Once the system is successfully booting from the Windows XP boot manager, then you can delete the files bootmgr and the folder /boot in the root of the active partition.

If you do choose #2 then, to be complete, you could also do a fixmbr command from the XP recovery console to replace the Vista/W7 MBR with the older XP MBR, but this isn't strictly necessary; both will accomplish the same thing. The Vista MBR has a few bytes of additional code to handle booting when Bitlocker is in use.
Mark

X61T 7764-CTO, Core 2 Duo L7500 LV 1.6 GHz, 4 GB RAM, 120 GB Intel X25M SSD
Multiboot w/Grub4DOS -- Windows 10, MustangPE, PartedMagic
My ex: X41T (2005 - 2009)

parleyp
Posts: 14
Joined: Tue Aug 25, 2009 7:29 pm
Location: Lake Mary, FL

Re: W7 shifts Drive Letters

#13 Post by parleyp » Sun Oct 18, 2009 5:16 pm

RealBlackStuff wrote:Even more BS.
It is MY PC and I should have full access to MY installation!
I'm not sure if I'm going to like W7 if it doesn't behave better. :BAAAD!:

And the Drive-letter shift is the worst case of bad behavior I have seen in many years!
If W7 wants to be on the C-drive (while installed on the F-drive), it should have ONLY swapped C and F.
Bad start :evil: :evil:

I won't play with W7 until next week..., so I'll just sit at my PC during boot to select my OS.
It seems pretty clear to me that you haven't had enough time to learn the new OS yet

You have access to your full installation...the reason for the folders was already explained a couple posts above. Drive letter positioning as described here has been a reality in MS world for 15 years. All Windows based systems do this....the only exception I ever found was win2k if you installed it twice into two different partitions...it seemed to somehow keep them straight. Also as already explained above, you are free to change the driver letter mapping for all drives except the system drive and map them the way you want them. I routinely do this so that I get the cd rom out of the middle of my multiple partition setup.

I suggest that you play with windows 7 in a virtual machine until you understand it better and take your time. It is NOT windows XP or Vista and is a huge improvement over both of them in my opinion. Good luck and keep asking questions.

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 21824
Joined: Mon Sep 18, 2006 5:17 am
Location: Wexford, Éire
Contact:

Re: W7 shifts Drive Letters

#14 Post by RealBlackStuff » Mon Oct 19, 2009 7:46 am

I'm sure there are a lot of things different between XP and W7.
I never even had a LOOK at Vista, so I have no idea about that "unwanted child".

As to drive letter shifting, even XP behaved perfectly if you install it on a different-from-C partition!
I have been working/playing with computers and PCs since 1968, and (except Vista) know most of the M$ quirks!
Drive-letter shifting was never an item until (probably Vista and) W7!
I see no reason at all why W7 should do such a stupid thing!
Either way, it's a moot point.
I have already removed W7 (it was only a limited-time RC version anyway).
It won't put it on my PC now until at least W7-SP1 has come out!
After all, I only 'converted' to XP in 2005.
Call me old-fashioned, but I'm rather safe than sorry.
Still NOT a great day for a Guinness! (the Real Black Stuff).
Ireland is on FULL lockdown until Easter 2021!
Covid-19: Stay safe, so Mask it or Casket!

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 21824
Joined: Mon Sep 18, 2006 5:17 am
Location: Wexford, Éire
Contact:

Re: W7 shifts Drive Letters

#15 Post by RealBlackStuff » Sun Oct 25, 2009 7:01 am

Additional info to remove the x:\Boot directory as well as bootmgr:
After running the recovery console with fixmbr and fixboot
- you need to DISable Simple Filesharing
- you need to take ownership of the above directory & file
- only now can you finally Delete those pesky suckers!
Still NOT a great day for a Guinness! (the Real Black Stuff).
Ireland is on FULL lockdown until Easter 2021!
Covid-19: Stay safe, so Mask it or Casket!

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “Windows 7”

Who is online

Users browsing this forum: No registered users and 4 guests