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STOP Error 7B when booting from USB floppy

ElForesto asked
Medium Priority
Last Modified: 2007-12-19
I'm attempting to rescue the registry on a Windows 2000 laptop using Microsoft's registry repair tool (http://www.microsoft.com/downloads/details.aspx?displaylang=en&familyid=56d3c201-2c68-4de8-9229-ca494362419c). I followed the instructions to make a set of Windows XP Pro setup boot floppies, and then installed the tool on disk 6 as directed. Since the laptop doesn't have a built-in floppy, I'm using a USB Sony floppy drive. It boots and loads the first five floppies just fine, but once it gets to disk 6, I get the following:

*** STOP: 0x0000007B (0xF898963C, 0xC0000034, 0x00000000, 0x00000000)

I'll guess that the boot process somehow loses the floppy during startup. I checked to see which drivers this USB floppy uses, and it appears to use built-in drivers when using Win2K, and the files it uses are present on the XP startup disks. I'd really like to simply revive this laptop instead of reloading Win2K on it, as backing up data over the network using ERD Commander sounds like a whole lot of "not having fun". If there is a way to trick Windows into thinking that the floppy is a normal drive, I'm all for that.

The laptop is a Dell Latitude D400.

Any insights are greatly appreciated!
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Pete LongTechnical Architect
Distinguished Expert 2019

This problem may occur if one or more of the following conditions exists:
Your computer is infected with a boot sector virus.
A device driver required by your boot controller is not configured to start at boot time or is corrupt. If during a WINNT /B installation no mass storage device was detected.
A resource conflict exists between the boot controller and another controller in the system or between SCSI devices.
Drive translation is not being performed or was changed.
The boot volume is corrupt and cannot be mounted by Windows NT.
Information in the Windows NT registry about which device drivers load at start up is corrupt.
If this error occurred during Windows NT Setup while reading Windows NT Setup floppy disk 2, you may have the Drive Swapping option enabled in your computer BIOS.
Using winnt /b as the installation method may present a timing issue for the disk controller. The controller is not given enough time to respond and identify itself and is therefore detected incorrectly or not at all.
If you run Setup from a bootable SCSI CD-ROM drive, you receive a STOP 7B error message because Setup does not allow you to add a third-party SCSI driver when you boot from the SCSI CD-ROM.
To resolve this problem, use the appropriate method:

Method 1
Check any diskettes for viruses that may have been used in the computer since the last time you were able to successfully restart Windows NT.

NOTE: You may need to use more than one brand of virus detection software to detect and remove various viruses.

If a virus has infected the Windows NT computer and a virus detection program cannot remove the virus and repair the system, you will have to reinstall Windows NT. For more information on how to protect the boot sector from viruses in Windows NT, see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: 122221
TITLE : How to Protect Boot Sector from Viruses in Windows NT

Method 2
Windows NT requires a mini-port driver to communicate with the boot controller. If the device driver is corrupt or incompatible with your controller, you can replace it by copying a new drive to the %systemroot%\system32\drivers folder or through the Emergency Repair process. On computers running on a SCSI controller or ATAPI enabled systems, SCSIPORT.SYS and DISK.SYS (Windows NT 4.0 only) device drivers are also required to successfully boot.

If you attempt a "WINNT /B" installation, you may receive a STOP 0x7B before mass storage detection takes place. To work around this, when the computer reboots after the initial file copy, press F6 as soon as "Setup is inspecting your computers hardware configuration" is displayed. This will allow you to add a mass storage device at the very beginning of text mode setup.

ARTICLE-ID: 125933
TITLE : STOP 0x0000007B: Inaccessible Boot Device After Removing CD-ROM

ARTICLE-ID: 164471
TITLE : Replacing System Files Using a Modified Emergency Repair Disk

Method 3
If an IRQ or I/O port address conflict exists between your boot controller and another controller in the system, Windows NT will either hang or stop with the Stop 0x0000007B error message. If you recently added new hardware, remove the new hardware or re-configure it so it does not conflict with the resources of any other installed controllers.

Check the SCSI chain for proper termination. Remove any non-essential SCSI devices or check to ensure each SCSI ID is unique.

ARTICLE-ID: 102651
TITLE : Required Settings for Adaptec 1510 SCSI Host Adapter

Method 4
The Windows NT Boot partition must exist within the first 1024 cylinders of the boot device. This is due to restrictions of the INT-13 BIOS call used to start the operating system. Check your CMOS settings for LBA support on IDE based systems, or your SCSI controllers BIOS settings for enabling drive translation for drives greater than 2GB.

ARTICLE-ID: 114841
TITLE : Windows NT Boot Process and Hard Disk Constraints

Method 5
If the file system is corrupt and Windows NT cannot mount the boot volume during start, move the drive to another machine running Windows NT and run the CHKDSK command on that drive. Alternately, attempt to create a parallel installation of Windows NT on the drive in a separate directory. The Windows NT Setup program checks the integrity of the volume prior to copying files and may fix some problems.
Method 6
If the SYSTEM Hive in the Windows NT registry is corrupt, it may prevent Windows NT from loading the Mini-port device driver required by the boot controller. To resolve this problem, use one of the following methods:

Start from the three Windows NT setup disks and use the Repair utility. When prompted, select to inspect registry files, and then only replace the System Configuration Registry hive. This hive contains information about which device drivers and services start during start up.
Install a parallel copy of Windows NT into a separate directory, and then use Registry Editor to modify the System hive in the Windows NT registry to correct the invalid or missing information.

ARTICLE-ID: 165748
TITLE : How to Disable a Service or Device that Prevents NT from Booting

Method 7
Many computers are equipped with a 5.25-inch and a 3.5-inch floppy diskette drive in one single unit. When you install Windows NT on a computer with this floppy drive unit, the STOP 0x7B error message may appear during Setup while Windows NT Setup disk 2 is being read. To resolve this problem, disable the Drive Swapping option in your system BIOS. For information about correcting this problem, see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: 126423
TITLE : STOP: 0x0000007B "Inaccessible_Boot_Device" During Setup Disk2

Method 8
Install using the three boot floppies, a bootable CD, winnt or winnt32. Install the device driver recommended by hardware vendor if one is available.
Method 9
Install using the three boot floppy disks. Install the device driver recommended by hardware vendor if one is available.

Additional query words: 3.50 3.51 4.00 0x7B Virus trap stop ntfaqset kbtshoot

Keywords: kbprb kbusage KB122926
Technology: kbAudDeveloper kbSBServ400 kbSBServ400a kbSBServSearch kbwin2000Pro kbwin2000ProSearch kbwin2000Search kbwin2000Serv kbwin2000ServSearch kbWinNT350search kbWinNT351search kbWinNT400search kbWinNTS350 kbWinNTS350search kbWinNTS351 kbWinNTS351search kbWinNTS400 kbWinNTS400search kbWinNTsearch kbWinNTSsearch kbWinNTW350 kbWinNTW350search kbWinNTW351 kbWinNTW351search kbWinNTW400 kbWinNTW400search kbWinNTWsearch


That's all great information... but it doesn't apply to my particular problem. The setup environment theoretically should supprt this USB floppy out of the box, and since it seemingly does not, I need to know how to add that support to the setup disks. Method 2 comes close to addressing my problem, but it's talking about replacing files on the hard drive which does little to help with booting from floppies.

While I appreciate the thought, I have already done the prerequisite legwork of using the MSKB, Google, and misc. resources I have bookmarked. EE is my last resort when I just can't figure it out otherwise. :)
Pete LongTechnical Architect
Distinguished Expert 2019

DO you have a CD drive in this PC?


Yes, I have a CD-ROM drive. I was trying to figure out how to transform the 6-floppy set (with the registry repair tool) into a usuable boot CD, though I had no success.
Pete LongTechnical Architect
Distinguished Expert 2019

YOu can boot from the CD and get to the recovery console, Im just curious why you are going down the boot floppy route?


The recovery console will not allow me to run the utility in question, nor can I run the automated repair from the 2000 CD as it will not locate the Win2K installation. The instructions above detail making XP Pro boot floppies to run this repair utility, so that's what I followed.
Technical Architect
Distinguished Expert 2019
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I followed those instructions (the SOFTWARE hive is the damaged one, BTW), and I get into the GUI now, though it takes some time to log on. Certainly a far cry from a blue screen or not being able to logon, the latter of which was the result of attempting to restore SOFTWARE from software.sav. I would still like to be able to repair the old SOFTWARE hive so that I don't have to reinstall all the apps on it.

Any thoughts on what to do in order to get that going?
Pete LongTechnical Architect
Distinguished Expert 2019

Progress :)

repair procedures tend to be aimed at the OS as opposed to applications :) From add remove software do you have repair options? on the apps you are concerned with?


It looks like I'm resigned to reinstalling most of the apps to get them to work properly. Half the programs aren't even listed in Add/Remove Programs anymore. However, I can live with making the end user reinstall her apps instead of me reinstalling Win2K. Thanks for the help!
Pete LongTechnical Architect
Distinguished Expert 2019

Glad I could help - if even in a small way


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