Routing and Remote Access Service Does Not Enforce Strong Encryption for Dial-Up Networking Clients

ID: Q177670

The information in this article applies to:

Microsoft Windows NT Server version 4.0
Microsoft Routing & Remote Access Service Update for Windows NT Server version 4.0
Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

When a Dial-Up Networking (DUN) client connects to a 40-bit or 128-bit Routing and Remote Access Server that is configured to "Require Data Encryption" or "Require Strong Data Encryption", the client is not disconnected if the selected data encryption negotiation fails to converge.

The following error may be logged in Event Viewer in the System Log on the server after the client has successfully established its connection:


   Event ID   : 20073
   Source     : Router
   Description: The following error occurred in the %protocol_name% module
                on port %port_name%. The PPP control protocol for this
                network protocol is not available on the server.

NOTE: This error may also be logged after the installation of the Routing and Remote Access Service Hotfix Update 1.0 if "Require Strong Data Encryption" is enabled.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. 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

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

Microsoft has confirmed this to be a problem in the Routing and Remote Access Service for Windows NT Server version 4.0.

This problem has been corrected in the RRAS Upgrade for Windows NT Server 4.0 Hotfix Pack 3.0 or later. For your convenience, the English version of this post-SP3 hotfix has been posted to the following Internet location. However, Microsoft recommends that you install Windows NT 4.0 Service Pack 4 to correct this problem.

ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/nt40/hotfixes-postSP3/rras30-fix/

MORE INFORMATION

For additional information, please see the following articles in the Microsoft Knowledge Base:

ARTICLE-ID: Q189594
TITLE : RRAS Upgrade for WinNT Server 4.0 Hotfix Pack 3.0 Release Notes

ARTICLE-ID: Q169895
TITLE : Enabling 128-bit Encryption for Routing and Remote Access

ARTICLE-ID: Q174474
TITLE : Installing RRAS Disables 128-bit RAS Encryption

Additional query words: steelhead steel head rras

Keywords : kbinterop NT4SP4Fix ntras kbbug4.00 kbfix4.00.sp4 NTSrv
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug