Programs with Reserved Windows Filenames May Not Run (86181)


The information in this article applies to:

  • Microsoft Windows 3.1
  • Microsoft Windows 3.11
This article was previously published under Q86181

SUMMARY

In Microsoft Windows version 3.1, if a program's executable filename is a name that is reserved by Windows, the file will not run. There is no error message associated with this behavior.

In addition, if a program's executable file has a name that is already running in memory and the program running in memory can only occur once, the duplicate program will:

  • not execute
  • not return an error message
  • may execute the duplicate program

MORE INFORMATION

This occurs because when Windows gets the request to run a new program, it checks for another occurrence of this program in memory. It does this by looking at the first eight characters of the filename and then comparing the information to the programs in memory.

If Windows finds another version of this program in memory, it sends this new instance to the currently running program. It is then up to this program whether or not to execute a new instance. If the program is set up to make itself active, then it will become active. If the program is reserved by Windows or its operating system, such as KERNEL.EXE, then the new program will not execute.

Unusable executable filenames:

CGA40WOA.EXE
COMM.EXE
COMMDLG.EXE
GDI.EXE
DISPLAY.EXE
DOSAPP.EXE
FIXFONTS.EXE
FONTS.EXE
KERNEL.EXE
KEYBOARD.EXE
MMSYSTEM.EXE
MOUSE.EXE
PROGMAN.EXE
SHELL.EXE
USER.EXE

There may be other executable filenames that cannot be duplicated, depending on the configuration and third-party applications.

KBCategory: kbother kbdisplay kbprb
KBSubcategory: win31
Modification Type:MajorLast Reviewed:10/15/2003
Keywords:KB86181
©2003 Microsoft Corporation. All rights reserved.