DOCUMENT:Q191890 TITLE :How To Obtain the Checked Build of Latest WinNT 4.0 Service Pack PRODUCT :Microsoft Windows NT PROD/VER:4.0 SP4 OPER/SYS:WINDOWS KEYWORD :kbfile ntdistrib kbinfo -------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0 Service Pack 4 - Microsoft Windows NT Workstation version 4.0 Service Pack 4 -------------------------------------------------------------------------- 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 4 has been posted to the following Internet location as Sp4chki.exe (x86), Sp4csymi.exe (Symbol files for x86), Sp4chka.exe (Alpha), and Sp4csyma.exe (Symbol files for Alpha): ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40 /ussp4/checked/ NOTE: The above link is one path; it has been wrapped for readability. For information on how to obtain the free build of the latest Windows NT 4.0 service pack, please see the following article in the Microsoft Knowledge Base: ARTICLE-ID: Q152734 TITLE : How To Obtain the Latest Windows NT 4.0 Service Pack Additional reference words: 4.00 sp4 servpack ntdistrib ============================================================================ 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.