Microsoft KB Archive/103927

From BetaArchive Wiki

Windows 3.0 and 3.1 Control Panel Files Do Not Work


The information in this article applies to:

  • Microsoft Windows NT Server version 3.1
  • Microsoft Windows NT Workstation version 3.1
  • Microsoft Windows NT Advanced Server, version 3.1

WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.


Windows 3.0 and 3.1 Control Panel (.CPL) files are not compatible with Windows NT even though they use the same extension.

While you are using Windows NT, if any Windows 3.0 or 3.1 Control Panel files are located in either of the WINNT\SYSTEM or SYSTEM32 subdirectories, you may receive the following error message:

The application or DLL DosDevices\C:\winnt\system\filename.cpl is not a valid Windows NT image. Please check this against your installation diskette.

The filename of the .CPL file depends on the application that installed it.


If an application, during its installation, places a .CPL file in the WINNT\SYSTEM directory and makes its appropriate entries in the Registry, you will receive the above error message when you try to run Control Panel. The installation program thinks it is writing its settings to an .INI file, but these settings are mapped by Windows NT to the Registry. Therefore, when you try to run Control Panel, Windows NT uses those mappings to look in the WINNT\SYSTEM directory for the .CPL file.

For this reason, copying a Windows 3.0 or 3.1 .CPL file into the WINNT\SYSTEM directory does not generate this error message.

Also, when Control Panel loads, it searches the WINNT\SYSTEM32 directory for any .CPL files. Any Windows 3.0 or 3.1 .CPL file located in the SYSTEM32 directory also generates the above error message.


To avoid this error message, use one of the following workarounds:

  • Remove the .CPL file from the WINNT\SYSTEM or SYSTEM32 directory.
  • Remove the appropriate entry from the Registry using the Registry Editor (REGEDT32.EXE). The location of the entry will vary, although it should be under the following path:

    HKEY_CURRENT_USER\Control Panel\

CAUTION: Modifying the Registry can harm your system. For details, query on the following words in the Microsoft Knowledge Base:

ntregistry and warning

Additional query words: prodnt 3rdparty third party third-party

Keywords : kbtool
Issue type :
Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW310 kbWinNTSsearch kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS310xsearch kbWinNT310xSearch kbWinNTW310Search

Last Reviewed: October 27, 2000
© 2001 Microsoft Corporation. All rights reserved. Terms of Use.