Q195050: How to Clear Environment Variables Using Setx.exe

Article: Q195050
Product(s): Microsoft Windows NT
Version(s): WINNT:4.0
Operating System(s): 
Keyword(s): kbenv kbtool
Last Modified: 10-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 4.0 
- Microsoft Windows NT Server version 4.0 
- Microsoft Windows NT Server, Enterprise Edition version 4.0 
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SUMMARY
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This article describes how to use the Setx.exe tool to clear both user and
system environment variables. Setx.exe is included with the Windows NT 4.0
Resource Kit.

MORE INFORMATION
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To clear an environment variable using Setx.exe at a command prompt:

1. Click Start, point to Programs, and then click Command Prompt.

2. If you want to clear a user environment variable, type the following line

  setx <variable> ""

  where <variable> is the user environment variable.

3. If you want to clear a system environment variable, type the following line

  setx <variable> "" -m

  where <variable> is the system environment variable.

4. Close the command prompt.

When you use Setx.exe to clear an environment variable value, the environment
variable name is not affected.

Additional query words: set null

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Keywords          : kbenv kbtool 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search kbWinNTS400
Version           : WINNT:4.0
Issue type        : kbhowto

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