Executable File Does Not Run from the Command Prompt in Windows NT (246766)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you attempt to run an executable file or a batch file from the command prompt on a computer running Microsoft Windows NT Server 4.0 or Windows NT Workstation 4.0, the file may not run. When you then attempt to run the executable file from the Autoexec.bat file, using the %pathext% variable, the file still may not run.

CAUSE

This behavior can occur when a value is missing from the following registry key:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session
 Manager\Environment

RESOLUTION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To resolve this issue, add the pathext value to the Environment key in the registry:

Start Registry Editor (Regedt32.exe) and locate the following key:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session
 Manager\Environment

Add the value to the registry key:
1. On the Edit menu, click Add Value.
2. In the Value Name box, type the following:
  PATHEXT=.COM;.EXE;.CMD;.BAT
  NOTE: Add any extensions that need to be executable.
3. In the Data Type list, click REG_SZ, and then click OK.
Quit Registry Editor, and then restart the computer.