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Q169171: Long PATH Environment Variable Causes 16-bit Apps to Hang

Article: Q169171
Product(s): Microsoft Windows NT
Version(s): WinNT:4.0
Operating System(s): 
Keyword(s): 
Last Modified: 09-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 
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SYMPTOMS
========

Certain 16-bit programs may stop responding (hang) or not run. When you look at
Processes in Task Manager, it shows NTVDM at or around 100 percent CPU time.

CAUSE
=====

This problem occurs when the PATH statement is approximately 200 characters or
more in length.

This problem has also been seen when security on the files in the
%SystemRoot%\System32 folder has been made too restrictive. Specifically, the
users running 16-bit programs must have at least Read (RX) access to all files
in the folder and all subfolders. This is the configuration by default.

RESOLUTION
==========

Use one of the following methods to resolve this problem:

Method 1
--------

The PATH statement can be found in two locations. Shortening one or both
statements should fix the problem.

PATH in System Properties:

1. In Control Panel, double-click the System icon. Click the Environment tab.

2. Under System Variables, select PATH and shorten the value.

3. Click Set, and then click OK.

PATH in Autoexec.nt:

1. Use Notepad to open Autoexec.nt, which is located in the
  %SystemRoot%\System32\Autoexec.nt directory.

2. Shorten any PATH= statement.

3. Save Autoexec.nt.

The NTVDM must be terminated before the new PATH will be used. To terminate the
NTVDM process, go to task manager and select NTVDM. Click End Process.

Method 2
--------

Increase the environment size in Config.nt:

1. Use Notepad to open Config.nt, which is located in the %SystemRoot%\System32
  directory.

2. Add the following statement:

     SHELL=%systemroot%\system32\command.com /e:2048

This will increase the environment size to allow the path statement to remain at
the current length. If problems persist, increase the e: parameter.

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT version 4.0.


Additional query words: slow DOS hang VDM
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Keywords          :  
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : WinNT:4.0
Issue type        : kbbug
Solution Type     : kbpending

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