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Article ID: 319458 - Last Review: May 18, 2007 - Revision: 1.3

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If you configure a Software Restriction policy to restrict access to a 16-bit program such as or, users can still start the program even though they are not permitted to run it.


Commands that run in the Virtual DOS Machine (Ntvdm.exe) are not recognized by Software Restriction policies.


To resolve this problem, obtain the latest service pack for Windows XP. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
322389  ( ) How to Obtain the Latest Windows XP Service Pack
The English version of this fix should have the following file attributes or later:
   Date         Time   Version      Size     File name
   09-Apr-2002  00:50  5.1.2600.42  898,560  Kernel32.dll



To work around this problem, restrict access to Ntvdm.exe by using access control lists (ACLs) at the file-system level. Note that using this method blocks all 16-bit code.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows XP Service Pack 1.


Note that you cannot use Software Restriction policies to prevent code from being run outside the Win32 subsystem. For example, user can run the same command from the POSIX subsystem. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
101270  ( ) Disabling the POSIX Subsystem

  • Microsoft Windows XP Home Edition
  • Microsoft Windows XP Professional
kbhotfixserver kbqfe kbbug kbfix kbsecurity kbwinxpsp1fix KB319458
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