DOCUMENT:Q191890  09-AUG-2001  [winnt]
TITLE   :How To Obtain the Checked Build of Latest WinNT 4.0 Service Pack
PRODUCT :Microsoft Windows NT
PROD/VER::4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4,4.0 SP5,4.0 SP6a
OPER/SYS:
KEYWORDS:

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Windows NT Workstation versions 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4, 4.0 SP5, 4.0 SP6a 
 - Microsoft Windows NT Server versions 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4, 4.0 SP5, 4.0 SP6a 
-------------------------------------------------------------------------------

SUMMARY
=======

Checked binaries provide error checking, argument verification, and system
debugging code not present in the free binaries.

Much of the additional code in the checked binaries is in the form of ASSERT
macros that test an expression. If the expression evaluates to FALSE, the macro
generates a kernel debugger error message and breaks into the debugger. This
lets you immediately determine the cause and location of the error.

Use the free and checked builds of Windows NT as follows:

 - Use the free build on the host machine, running WinDbg.

 - Use the free build to develop and build a driver. Performance suffers in the
   checked build due to the additional code that is executed.

 - Use the checked build on the target computer to test and debug a driver
   during the initial phases of its development.

 - Use the free build on the target computer to test and debug your driver
   during the final phases of its development. The final testing of your driver
   must be done on a free version of the driver running the free build of
   Windows NT.

The extra protection of the checked build of Windows NT carries some penalties.
Because of the additional error checking code and debugging information, the
checked binaries are larger and run slower than the free binaries. This can
conceal synchronization or other timing-related problems, such as race
conditions, that become apparent only in the free build.

If you run the checked build of Windows NT without having enabled kernel
debugging, unexpected system shutdowns can occur. This is because the additional
checks in the checked build increase the likelihood of encountering a
breakpoint.

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

The checked build of Windows NT 4.0 Service Pack 6a has been posted to the
following Internet location:

   http://www.microsoft.com/ntserver/nts/downloads/recommended/SP6/SP6build/default.asp

For additional information on how to obtain the free build of the latest Windows
NT 4.0 service pack, click the article number below to view the article in the
Microsoft Knowledge Base:

   Q152734 How To Obtain the Latest Windows NT 4.0 Service Pack

Additional query words: 4.00 sp6a servpack ntdistrib

======================================================================
Keywords          :  
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400search kbWinNT400search kbWinNTW400sp5 kbWinNTW400sp4 kbWinNTW400sp3 kbWinNTW400sp2 kbWinNTW400sp1 kbWinNTSsearch kbWinNTS400sp6 kbWinNTS400sp5 kbWinNTS400sp4 kbWinNTS400sp3 kbWinNTS400sp2 kbWinNTS400sp1 kbWinNTS400search kbWinNTW400SP6a
Version           : :4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4,4.0 SP5,4.0 SP6a
Hardware          : ALPHA x86
Issue type        : kbinfo

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 2001.