If you configure a Software Restriction policy to restrict access to a 16-bit program such as Command.com or Edit.com, 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:
How to Obtain the Latest Windows XP Service Pack
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix. Note
If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note
The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
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:
Disabling the POSIX Subsystem