DOCUMENT:Q198524  10-AUG-2001  [winnt]
TITLE   :Large Ntbootdd.sys File May Cause Problems
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:4.0
OPER/SYS:
KEYWORDS:kbenv

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The information in this article applies to:

 - Microsoft Windows NT Server version 4.0 
 - Microsoft Windows NT Workstation version 4.0 
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SYMPTOMS
========

When you use the SCSI() syntax in the Boot.ini file to boot a computer using a
SCSI adapter that does not have INT 13h BIOS support, the computer may stop
responding (hang). In Windows NT 4.0, you may receive a "Trap E" message.


Some SCSI adapters have partial INT 13h BIOS support, in that the BIOS supports
only two disk drives. The problem can occur when you try to boot from a drive
not supported by the BIOS.

CAUSE
=====

The SCSI() syntax requires the Ntbootdd.sys file. If the size of the
Ntbootdd.sys file exceeds approximately 64 kilobytes (KB), the problem may
occur.

RESOLUTION
==========

To work around this issue, try any of the following methods:

 - Verify that the size of the Ntbootdd.sys file is less than 64 KB.

 - Use a SCSI adapter with full INT 13h BIOS support.

 - Boot using a disk supported by the BIOS.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products that are
listed at the beginning of this article.

MORE INFORMATION
================

The Ntbootdd.sys file is not required if the SCSI adapter has INT 13h BIOS
support. The Ntbootdd.sys file is a renamed copy of the SCSI device driver
located in the root folder. This file is also used with Windows NT Startup
floppy disks.

======================================================================
Keywords          : kbenv 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0
Issue type        : kbprb
Solution Type     : kbpending

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