DOCUMENT:Q242096  10-AUG-2001  [winnt]
TITLE   :Cannot run System Editor.
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:4.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

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

When you attempt to run Sysedit.exe from the command line or from the Run dialog
box, nothing may happen.

CAUSE
=====

Sysedit.exe is a 16-bit program. If any of the .dll files listed in the
KnownDLLs value in the following registry key are missing or corrupted, the
Windows NT Virtual DOS Machine (NTVDM), which is required to run 16-bit
programs, does not run properly:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\WOW

The same problem occurs if the Config.nt or Autoexec.nt file is missing or
corrupted, or contains unexpected values.

RESOLUTION
==========

To resolve this issue:

1. Make sure that all of the .dll files listed in the KnownDLLs value in the
   following registry key are uncorrupted and present in either the
   %SystemRoot%\System32 or the %SystemRoot%\System folder:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\WOW

2. To replace any missing files, copy them from a Windows NT 4.0-based computer
   that has a properly working NTVDM to the %SystemRoot%\System32 and
   %SystemRoot%\System folders.

   NOTE: Not all of the .dll files in the list reside in both the System32 folder
   and the System folder, but many do. It does not harm your computer to have
   them duplicated in both folders.

3. If no files are missing, ensure that all the files are uncorrupted by
   replacing them with the same files from a Windows NT 4.0-based computer that
   has a properly working NTVDM.

4. Restart the computer.

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

The files listed in the KnownDLLs value include:

   Comm.drv
   Commdlg.dll
   Ctl3dv2.dll
   Ddeml.dll
   Keyboard.drv
   Lanman.drv
   Mapi.dll
   Mmsystem.dll
   Mouse.drv
   Netapi.dll
   Olecli.dll
   Olesvr.dll
   Pmspl.dll
   Shell.dll
   Sound.drv
   System.drv
   Toolhelp.dll
   Vga.drv
   Wfwnet.drv
   Win87em.dll
   Winoldap.mod
   Winsock.dll
   Winspool.exe
   Wowdeb.exe
   Timer.drv
   Rasapi16.dll
   Compobj.dll
   Storage.dll
   Ole2.dll
   Ole2disp.dll
   Ole2nls.dll
   Typelib.dll
   Msvideo.dll
   Avifile.dll
   Msacm.dll
   Mciavi.drv
   Mciseq.drv
   Mciwave.drv
   Progman.exe
   Avicap.dll

Additional query words: 16-bit ntvdm wow system

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0
Issue type        : kbprb

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

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