Incorrect Routing Table When You Connect to Some VPN Servers (300561)

SYMPTOMS

If you make a virtual private network (VPN) connection to certain non-Microsoft VPN servers, you may not be able to send data over the VPN connection. The problem also occurs if you are making a one-way dial-on-demand connection from a Windows 2000-based server that is running the Routing and Remote Access service to certain non-Microsoft VPN servers. You may be able to establish a VPN connection, but you do not have connectivity and the VPN connection is dropped after a time-out period.

This problem only occurs when the VPN client is running one of the following programs:

Windows 2000 that is using Internet Connection Sharing.
Windows 2000 Professional that has the Incoming Connections functionality turned on.
Windows 2000 Server that has Routing and Remote Access installed.

Standard Windows 2000-based VPN clients that are not running the Routing and Remote Access service do not experience this problem.

CAUSE

This problem occurs if the non-Microsoft VPN server is using the same Internet Protocol (IP) address for both its Internet Protocol Control Protocol (IPCP) server and its network interface. In this scenario, the local routing table is incorrectly updated during the connection. Although the Request for Comments (RFC) is not clear about how to handle this scenario, this scenario is not a standard implementation of VPN. Windows 2000 is not designed to handle this scenario.

RESOLUTION

Service Pack Information

To resolve this problem, obtain the latest service pack for Microsoft Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to Obtain the Latest Windows 2000 Service Pack

Hotfix Information

NOTE: Microsoft recommends that you apply the hotfix that is described in this section to only a Windows 2000-based computer that has Service Pack 3 (SP3) installed.

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Windows 2000 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

The English version of this fix should have the following file attributes or later:

 Date         Time   Version        Size     File name
 -------------------------------------------------------- 
 07-May-2003  15:24  5.0.2195.6606  159,504  Iprtrmgr.dll 
 07-May-2003  15:24  5.0.2195.6626  198,928  Rasppp.dll