STOP 0x0000007B: Inaccessible Boot Device After Removing CD-ROM

Article translations Article translations
Article ID: 125933 - View products that this article applies to.
This article was previously published under Q125933
Expand all | Collapse all


After you have installed Windows NT version with an IDE CD-ROM that is daisy chained with your IDE hard disk, and have configured the CD-ROM as a slave and the hard disk as the master, the following STOP message appears when you reboot after removing the CD-ROM:
STOP 0x0000007B
Inaccessible Boot Device


During the installation of Windows NT, ATAPI.SYS, not ATDISK.SYS, is copied to the <%systemroot%>\SYSTEM32\DRIVERS subdirectory.

If you encounter this error, always check to make sure that the system is not infected with a virus, particularly a boot sector virus.


Before you remove the IDE CD-ROM, do the following:

  1. If you are running Windows NT 3.5 or 3.51, go to the Windows NT Setup program and choose Add/Remove SCSI Adapters. If you are running Windows NT 4.0, go to the SCSI Adapters option in Control Panel.
  2. Select "IDE CD-ROM (ATAPI 1.2)" and choose Remove. Exit of Windows NT Setup, or the Control Panel.
  3. In Control Panel, choose the Devices icon.
  4. Select the device ATAPI and choose Startup. For Startup Type, select Disabled and choose OK.
  5. If there are no SCSI disks installed in the system, select the device SCSIDISK and choose Startup. For Startup Type, select Disabled and choose OK.
  6. Select the device ATDISK and choose Startup. For Startup Type, select Boot and choose OK.
  7. Copy ATDISK.SYS from the \I386 subdirectory of the Windows NT Server or Workstation version 3.5 CD to the <%systemroot>\SYSTEM32\DRIVERS subdirectory.
  8. Shutdown Windows NT and remove the CD-ROM. Change the jumper configuration on the hard disk from Master to Stand-alone.


Microsoft has confirmed this to be a problem in the Windows NT versions listed above. We are researching this problem and will post new information here in the Microsoft Knowledge Base if it becomes available.


Article ID: 125933 - Last Review: November 1, 2006 - Revision: 3.1
  • Microsoft Windows NT Workstation 3.5
  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Workstation 4.0 Developer Edition
  • Microsoft Windows NT Server 3.5
  • Microsoft Windows NT Server 3.51
  • Microsoft Windows NT Server 4.0 Standard Edition
kbhardware KB125933

Give Feedback


Contact us for more help

Contact us for more help
Connect with Answer Desk for expert help.
Get more support from