Registry Error, Cannot Boot.

[Techie23]

Operating System: Windows XP SP2

Ok, yesterday I found out that the drive letter of my HD was not C: and this caused an error in one of my programs.

However, since it is the boot drive, it doesn't allow you to change the drive letter easily. So I went about the more complicated way and used the Registry.

Here is the guide I used: http://leghumped.com/blog/2007/01/09/chang...-a-boot-device/

1. Go to the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices

2. Find the drive letter you want to change to (new). Look for "\DosDevices\C:".

3. Rename it to an unused drive letter "\DosDevices\Z:".

This frees up drive letter C.

4. Find the drive letter you want changed. Look for "\DosDevices\D:".

5. Rename it to the appropriate (new) drive letter "\DosDevices\C:".

6. Click the value for \DosDevices\Z:, click Rename, and then name it back to "\DosDevices\D:".

I realize exactly what I did. When I changed my drive letter I wanted to Z, and changed the drive I wanted (H:) to be C:, I made the mistake of not changing the Z drive back to H:

Now, whenever I boot, it actually loads the OS, but when it gets to the Windows Login screen it freezes.

The data on the computer needs to be intact, what would be the best way to go about fixing this? Best case scenario for me would be, being able to get back into the Registry and change the keys back.

Appreciate any help.

Edited April 14, 2009 by Techie23

[Matt]

Try a repair install:

http://www.besttechie.net/kb/entry/3/

That will keep your data intact.

Or, if you have a windows disk to boot from:

• # Open Command Prompt.
  # Type:
  diskpart
  # At the DISKPART prompt, type:
  list volume
  Make note of the number of the simple volume whose drive letter you want to assign, change, or remove.
  # At the DISKPART prompt, type:
  select volume n
  where n is the volume's number, whose drive letter you want to assign, change, or remove.
  # At the DISKPART prompt, type one of the following:
  assign letter=L
  Where L is the drive letter you want to assign or change.
  remove letter=L
  Where L is the drive letter you want to remove.