TCP/IP Source Routing Feature Cannot Be Disabled

ID: Q217336

The information in this article applies to:

Microsoft Windows NT Workstation versions 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4
Microsoft Windows NT Server versions 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4
Microsoft Windows NT Server, Enterprise Edition versions 4.0, 4.0 SP4
Microsoft BackOffice Server versions 4.0, 4.5
Microsoft Windows NT Server versions 4.0, 4.0 SP4, Terminal Server Edition

IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

SYMPTOMS

On a computer running Windows NT 4.0, you cannot disable the source routing feature for the TCP/IP protocol.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys and Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).

After you apply the fix referenced above, perform the following steps to enable and disable source routing:

Start Registry Editor (Regedt32.exe).

Locate the following key in the registry:


   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

On the Edit menu, click Add Value, and then add the following registry value:


   Value Name: DisableIPSourceRouting
   Data Type:  REG_DWORD
   Value:      0 , 1 or 2
   Note:       0 - enables source routing 
               1 - disables source routing when IP forwarding is also enabled
               2 - disables source routing completely (recommended for best security)

Quit Registry Editor.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Windows NT 4.0. This problem was first corrected in Windows NT version 4.0 Service Pack 5.

Additional query words:

Keywords : nt4sp5fix
Version : winnt:4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4,4.5
Platform : winnt
Issue type : kbbug