DOCUMENT:Q176321 09-AUG-2001 [winnt] TITLE :Unable to Resolve NetBIOS Names Through PPTP Connection PRODUCT :Microsoft Windows NT PROD/VER:winnt:4.0 OPER/SYS: KEYWORDS:kberrmsg kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== If the Windows Internet Name Service (WINS) server is on the same computer as the Point-to-Point Tunneling Protocol (PPTP) server, and you attempt to connect to a computer using a PPTP client, either or both of the following symptoms may occur: - The NetBIOS name of the computer to which you are attempting to connect is not resolved. - You receive an error message similar to the following error message: System error 53 has occurred. The network path was not found. If the WINS server is not on the same computer as the PPTP server and you attempt to connect to a computer using a PPTP client, you may be able to connect to computers on your local area network (LAN), but you may be unable to connect to network shares or resources on the PPTP server. CAUSE ===== This issue can occur if there is a host route added to the PPTP client that routes all Internet Protocol (IP) traffic destined for the PPTP server through your original dial-up connection to your Internet service provider (ISP). This path may contain routers or firewalls that block User Datagram Protocol (UDP) ports 137 or 138, or Transmission Control Protocol (TCP) port 139. These ports must be open for NetBIOS traffic to pass. RESOLUTION ========== To resolve this issue, use either of the following methods: Method 1 -------- Use the NetBEUI protocol for your PPTP tunnel instead of, or in addition to, TCP/IP. Method 2 -------- Enable unicast traffic through UDP ports 137 and 138 and TCP port 139 across all routers and firewalls between the PPTP client and PPTP server. NOTE: If you use this method, your PPTP client and server may be susceptible to unwanted traffic from other hosts. Please ensure that you enable the proper permissions and rights to secure your computers. Method 3 -------- If the WINS server is on the same computer as the PPTP server, move the WINS server to a different computer. NOTE: If UDP ports 137 and 138 and TCP port 139 are not enabled, you may be able to resolve the NetBIOS name of the PPTP server, but you may be unable to connect to its resources. Method 4 -------- Create an additional IP interface on the PPTP server. To do so, use any of the following methods: - Add a second network adapter to your PPTP server so that your PPTP clients can gain access to resources on the PPTP server using an IP address different from that of the PPTP server adapter. Be sure to disable the WINS client on the PPTP network adapter. - Add a Microsoft Loopback adapter to the PPTP server. Make sure it registers with WINS. - Add a second IP address to the existing network adapter in the Advanced TCP/IP Properties dialog box on the PPTP server. Make PPTP connection to the second IP address. For additional information, please see the following article(s) in the Microsoft Knowledge Base: ARTICLE-ID: Q133241 TITLE : Browsing Domain Master Browsers w/ Multiple NICs and Protocols ARTICLE-ID: Q135404 TITLE : Multihomed Master Browser May Cause Event ID 8021 and 8032 Additional query words: ntnetserv NTPROTOCOL NTSrv nttcp kberrmsg kbinterop kbnetwork ====================================================================== Keywords : kberrmsg kbnetwork Technology : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 Version : winnt:4.0 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.