RAS Server Cannot Use DHCP to Assign Addresses w/ PPTP Filtering (158387)
The information in this article applies to:
- Microsoft Windows NT Workstation 4.0
- Microsoft Windows NT Server 4.0
This article was previously published under Q158387 SYMPTOMS
PPTP clients are unable to connect to your PPTP server with the TCP/IP
protocol. The following error message is logged in the Event Viewer on the
PPTP server:
Event ID: 20091
Source: RemoteAccess
Description: The Remote Access Server was unable to acquire an IP
Address from the DHCP Server to be used on the Server Adapter. Incoming
users will be unable to connect using IP.
This problem will occur if you have two network interfaces on your PPTP
server, one connected to your internal network and the other connected to
the Internet, and PPTP filtering is enabled on the interface with a
connection to the Internet.
You enable PPTP filtering on the interface connected to the Internet to
disable this interface for non-PPTP traffic. The interface connected to
your internal network does not have PPTP filtering enabled; however, the
RAS Server service running on this machine is still unable to obtain an IP
address from the DHCP server for the RAS Server PPTP adapter.
CAUSE
DHCP traffic is sent via broadcast. On a computer with more than one
network interface, the Tcpip.sys driver incorrectly discards broadcast
packets when one of the network interfaces has PPTP filtering enabled.
Tcpip.sys should forward the broadcast packets to the non-PPTP filtering
interfaces instead of discarding the broadcasts.
RESOLUTION
To correct this problem, install Windows NT 4.0 service pack 2 or later.
STATUS
Microsoft has confirmed this to be a problem in Windows NT version 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):
| Modification Type: | Major | Last Reviewed: | 2/20/2002 |
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| Keywords: | kbnetwork KB158387 |
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