Login problem after changing HKLM\\SYSTEM\\MountedDevices.. Urgent help needed...

[undisclosed]

Hi,
Please help me...

Out of curiosity I swapped the naming of \DosDevices\C: and
\DosDevices\D: at HKEY_LOCAL_MACHINE\\SYSTEM\\MountedDevices in the
registry. After that the drive letters changed (as viewed from �My
Computer�) but during login in the system via telnet the prompt was
showing D:\WINNT\Profiles\Administrator> instead of
C:\WINNT\Profiles\Administrator>. Seeing this I reverted back the naming
of \DosDevices\C: and \DosDevices\D: at
HKEY_LOCAL_MACHINE\\SYSTEM\\MountedDevices. but after that during login
in the system via telnet the prompt was showing
G:\WINNT\Profiles\Administrator and at �My Computer� G: was showing to
have the disk of C: (disk label and size of C). Then I renamed
\DosDevices\G with \DosDevices\C. After that the login problem arose. As
soon as I login, the windows show applying your settings, saving your
settings and logs off automatically without logging in. I can't even
login in safe mood.

Please help me

--
squirrel

[John John - MVP]

From your remote computer can you access the administrative shares on
the bungled machine? \\ComputerName\c$ or \\ComputerName\d$ , etc?

If yes you can use Regedit to load the remote system hive of the bungled
machine. If you cannot remotely connect to the registry you will have
to mount the disk in another machine or use a PE disk with a registry
editor plug-in to try to fix this.

John

undisclosed wrote:
> Hi,
> Please help me...
>
> Out of curiosity I swapped the naming of \DosDevices\C: and
> \DosDevices\D: at HKEY_LOCAL_MACHINE\\SYSTEM\\MountedDevices in the

> registry. After that the drive letters changed (as viewed from �My
> Computer�) but during login in the system via telnet the prompt was

> showing D:\WINNT\Profiles\Administrator> instead of
> C:\WINNT\Profiles\Administrator>. Seeing this I reverted back the naming
> of \DosDevices\C: and \DosDevices\D: at
> HKEY_LOCAL_MACHINE\\SYSTEM\\MountedDevices. but after that during login
> in the system via telnet the prompt was showing

> G:\WINNT\Profiles\Administrator and at �My Computer� G: was showing to

[John John - MVP]

or you can do it the long tortuous way:

http://support.microsoft.com/kb/307545
How to recover from a corrupted registry that prevents Windows XP from
starting

John

[Anteaus]

Boot from a windows 98 disk and do 'fdisk /mbr'

"undisclosed" wrote:

> .
>

[John John - MVP]

A very good idea, that would be one of the easiest way around the problem!

John

[undisclosed]

Please see the attachments for the snapshots.

+-------------------------------------------------------------------+
|Filename: mounted_devices.JPG |
|Download: http://www.technologyquestions.com/technology/attachment.php?attachmentid=142|
+-------------------------------------------------------------------+

--
squirrel

[undisclosed]

Hi,
Thanks for the reply...
@John: Yes I can access \\ComputerName\d$ but I cannot access
\\ComputerName\c$. Also I can load the registry via "connect network
registry". What I see after loading the registry is, in
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
userinit is having address c:\winnt\system32\userinit.exe but in
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices there is no \DosDevices\C: . In
my machine C: and D: generally have almost same data with some
exceptions.
[image:
http://picasaweb.google.com/meowcat001/Test#5407947635681147874]
[image:
http://picasaweb.google.com/meowcat001/Test#5407947636237192498]
Please see the snapshots. Please help...

@Anteaus: I don't have any privilege to reinstall or doing any recovery
with installation disk. So, it will be a problem. But I have the
administrator access.
Please help..

--
squirrel

[undisclosed]

Also to be specific its a windows server 2003 machine.

--
squirrel

[John John - MVP]

We can't see these images without creating an account and logging on to
the site, something that many of us here will not be inclined to do.

John

[John John - MVP]

Save the registry key HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices to an
accessible location, just in case that you might want to restore it and
try different things if this suggested fix doesn't work.

Delete *all* the contents of the
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices key, do not delete the key
itself. *DO* NOT* change the userinit value at the Winlogon key!

Deleting all the entries at the MountedDevices key will force the Mount
Manager to reenumerate all the devices, the first active partition on
the disc will or should be assigned drive letter C: and the system
should boot normally. You will then have to redo your other drive
letters and reassign them to your liking.

John

PS. I don't know what this "PreventCyclicReb..." key is for, might be
perfectly legit but I haven't seen this type of value in the
MountedDevices key before. for my own curiosity what is the full name
of the value?

[undisclosed]

Hi,
Thanks a lot for the answers and \\ComputerName\d$ concept. I was able
to find a backup of the registry mounted devices in \\ComputerName\d$
(although i saved it previously in c:) and tried to restore with it's
information. As \DosDevices\C: and \DosDevices\G: were missing, I just
created these two keys with values taking from the backup. The backup
was taken after some changes were made in the registry so it was not the
backup of the original registry. After that, The system is letting me to
login. But the problem that still exists now is that, default prompt in
command prompt (or when i'm logging via telnet) is showing

D:\WINNT\Profiles\Administrator> instead of

C:\WINNT\Profiles\Administrator>. So, I think still I might need to swap
the values of C: and D: from mounted devies. But, I was suspicious and
thought I would take your suggestions about this.
And, John, I was in a hurry and I got your reply after I have done the
changes. I think, I should also try your showed steps of deleting all
the contents of the
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices key. Please suggest me what
should I do in such current situation.

And, as you requested, I got this in the registry. Sorry, I don't know
what is this for.
Value 30
Name: PreventCyclicReboot
Type: REG_DWORD
Data: 0

--
squirrel

[John John - MVP]

Personally I would have deleted all the entries in the MountedDevices
key, this should have done the trick.

*BUT* .... being that this is a server and being that I have no
knowledge of your hard disks and their configurations, and being that I
don't know what the PreventCyclicReboot is for, perhaps we should take a
more cautious approach.

Swap the letters at the \DosDevices\C: and \DosDevices\D: values. To
release the drive letter C assign the \DosDevices\C: another unused
letter, like Z, the letter C will be released and you will then be able
to assign it to the incorrect \DosDevices\D:, after you do this the D
letter will be released and you will then be able to swap it with the Z
letter that you assigned earlier. To save the changes don't forget to
unload the hive after you're done!

John

[undisclosed]

Hi,
Thanks for the help and patience.
Yes, I have swapped the letters at the \DosDevices\C: and
\DosDevices\D: and it worked...
Surely I would try the other process (deleting all entries in
mountdevices) in my personal computer ... thanks it is a good learning.

And, would you please tell me why at the very first time when I swapped
the naming of \DosDevices\C: and \DosDevices\D: the prompt was showing

D:\WINNT\Profiles\Administrator> instead of

C:\WINNT\Profiles\Administrator>?... Do I need to change any other
parameters in any places or is it normal to show the inverted prompt.
Thanks.

--
squirrel

[John John - MVP]

You're welcome, thanks for the follow up. I'm not sure why switching
the letters around the first time didn't work. You said that at that
point the system was unexpectedly assigned drive letter G:, I can only
surmise that you probably changed the drive letter on the wrong partition.

If the SET USERPROFILE and SET SYSTEM commands return the expected
information on the C:\ drive you need not change anything else as far as
the operating system and user profiles are concerned. Of course you
will have to see if your other partitions kept their original drive
letters. If the letters of your other partitions are not consistent
with their previous assignment you may have problems with some of your
scripts and drive mappings.

John

[undisclosed]

Hi John,
Sorry, I'm so late to post this reply. I think I have changed the drive
letters correctly. Anyway, if the system does not change the default
prompt should I change the prompt by these SET USERPROFILE and SET
SYSTEM commands or should I go back to original configuration and again
take another attempt to change the drive letters?
Thanks a lot.

--
squirrel

[John John - MVP]

You only want to use the SET command to confirm that your Windows
installation and the user profiles are on their same original drive letter!

The drive letter upon which Windows was installed is immovable, if the
Windows partition was assigned drive letter C when you installed Server
2003 the partition must always retain this C drive letter. By default
user profiles are on the same drive letter as the operating system and
unless you moved them they too should be on the same drive letter. If
the SET command reports that the operating system is on a different
drive letter then things are not right, you need to return the partition
to its proper drive letter. If things aren't right you could use System
Restore to restore the machine to a point before you did the initial
changes.

John