Nwrdr.sys Fails Reading File with Execute Only Attribute (157279)


The information in this article applies to:

  • Microsoft Windows NT Advanced Server 3.1
  • Microsoft Windows NT Workstation 3.1
  • Microsoft Windows NT Workstation 3.5
  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Workstation 4.0
  • Microsoft Windows NT Server 3.1
  • Microsoft Windows NT Server 3.5
  • Microsoft Windows NT Server 3.51
  • Microsoft Windows NT Server 4.0
This article was previously published under Q157279

SYMPTOMS

If a NetWare administrator changes the file attributes of executable files to Execute Only, the following error message appears on any Windows NT computer accessing the files through either Client Services for NetWare or Gateway Services for NetWare:
The system cannot find the file <drive>:\<directory>\<executable file>

CAUSE

Windows NT does not recognize the Execute Only file attribute.

WORKAROUND

To work around this problem:
  1. Rename or remove the executable file.
  2. Reinstall the file or restore the file from a previous backup.
Page 135 of the Novell NetWare version 3.11 "Utilities Reference" states the following: 
   ... once assigned, this attribute cannot be removed.

STATUS

Microsoft has confirmed this to be a problem in Windows NT versions 3.1, 3.5, 3.51, and 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K


Fixes are not available for Windows NT 3.1 or 3.5. Refer to the Workaround section of this article.

MORE INFORMATION

The default behavior explained above can be altered to allow Nwrdr.sys to read Execute Only files. The fix and a new registry parameter are required. The following instructions explain how to enable this functionality:

WARNING: Using the Registry Editor incorrectly can cause serious, system- wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.

  1. Rename the existing Nwrdr.sys file in the %Systemroot%\System32\Drivers directory.
  2. Copy the new Nwrdr.sys file to the same location.
  3. Add the following registry values by running Regedt32.exe.

    In HKEY_LOCAL_MACHI on Local Machine:

    Key Name: SYSTEM\CurrentControlSet\Services\NwRdr\Parameters Name: ReadExecOnlyFiles Type: REG_DWORD Data: 0
  4. Stop and restart Client Services for NetWare or Gateway Services for NetWare, depending on whether the fix is applied to Windows NT Workstation or Windows NT Server.
NOTE: Winfile.exe in Windows NT 3.51 and 4.0 will not display files with the X attribute. This was a pre-existing condition. The command prompt and Explorer.exe in Windows NT 4.0 will display files with the X attribute.
Modification Type:MajorLast Reviewed:4/9/2004
Keywords:kbnetwork KB157279
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