crashdebug?

gsenechal RemoveThis @gmail.com wrote:
> Hi all,
>
> I have a piece of manufacturing equipment that uses 2 computers to run
> its vision and CNC functions. One of the computers is having trouble,
> and I hope someone out there can offer some advice.
>
> Computer is running WINNT 4.0
> 3.5" Floppy drive
> 2 GB HD
> No CD-Rom
> No USB
> No network
>
> Error on boot up is: unable to load systemroot\system32\drivers\vga.sys

Sounds like you have a corruption on the HDD and one (or probably more)
system files are now damaged / missing

> The BSOD suggests I use the /crashdebug option. That sounds good but I
> can't figure out how to do that if I can't get past the BSOD. As I
> understand it, I need to add the /crashdebug line to the boot.ini file
> in the [operating systems] section (right?)

The /crashdebug option won't really help you. It merely puts the machine
into a diagnostic mode to allow software debugging - eg: you wrote a
programme that crashes the machine and you'd like to know why.

If you start the machine with the "Windows NT Version 4.00 [VGA mode]"
it adds the /basevideo /sos switches to the startup process and this
will give a verbose list of each step of the load process as it proceeds.

If the HDD is formatted FAT16 (at 2GB a possibility here) you could boot
the machine of a DOS floppy and manually replace damaged missing files
(obviously start with vga.sys)

If the HDD is formatted NTFS I suggest you do a 'parallel install' of
NT4 - assuming you have the required HDD space (about 100MB is required)
You may need to temporarily attach a CD-ROM drive to allow you to use a
Install CD to achieve this.

Once you have a working parallel NT system, you can examine and attempt
repair of the now damaged original installation.

You may find that this system was originally 'ghosted' by the
manufacturer and it may be easier to approach them about having the HDD
reimaged to the correct state.

> I've tried the NT4 boot disks, but after the detect mass storage step I
> get a message telling me I need a CD-Rom drive.
>
> The only idea I have, but haven't tried yet (because getting the hard
> drive out of this giant machine is a huge undertaking) is to pull the
> hard drive, hook it up to another system, and access the boot.ini file
> that way. We only have WinXP systems on site. Can I read an NT drive
> from an XP system?

Yes - you can read a NT4 HDD on a XP system BUT BEWARE - the first time
the system 'sees' the HDD it will 'upgrade' the NTFS file system to a
later version, which a NT4 system may not be able to read / access (at
least until NT4 is advanced to about SP5 if my memory serves me correctly)

I think it may be best to approach the manufacturer of the machine as a
first line of attack, they probably have all the tools at hand to
readily rebuild the HDD - I assume the machine has specific software for
CNC and related functions ?

Calvin.

gsenechal DeleteThis @gmail.com wrote:
> Calvin
>
> Thank you very much for your detailed response. I really appreciate
> it.
>
> Based on your input I've decided to do two things:
>
> - Order a new hard drive from the equipment manufacturer (all set-up
> with the OS and programs)
Probably the quickest way to get a working machine again - repairing a
'broken' file system can be a long and messy affair

> - Attempt to repair the current file system using the dos boot disk
> method.

This will only work if the HDD is formatted using FAT16 - which DOS can
recognise. If it is NTFS you will need to remove the drive and access
the files using another NT4 box, or perform a 'parallel install' on the
existing machine to be able to manipulate the files of the 'broken' OS.

Calvin.