DOCUMENT:Q322121  08-JUL-2002  [winnt]
TITLE   :Windows May Drop UDP Packets During a RAS Connection
PRODUCT :Microsoft Windows NT
PROD/VER::4.0,4.0 SP6a
OPER/SYS:
KEYWORDS:kbWinNT400nospFix

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The information in this article applies to:

 - Microsoft Windows NT Server versions 4.0, 4.0 SP6a 
 - Microsoft Windows NT Server, Enterprise Edition versions 4.0, 4.0 SP6a 
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SYMPTOMS
========

Under certain situations, User Datagram Protocol (UDP) network packets may be
discarded during a Remote Access Service (RAS) connection if the lower byte of
the source port of the UDP package equals 137.

CAUSE
=====

The component checks only the low byte of the source port to decide if a packet
is a NetBIOS packet. This can cause a false positive test because the source
port field is two bytes long.

RESOLUTION
==========

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 systems
that are experiencing this specific problem.

To resolve this problem, 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 usual 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 should have the following file attributes or
later:

   Date         Time   Version        Size    File name
   -----------------------------------------------------
   15-May-2002  15:56  4.0.1381.7159  12,976  Rasarp.sys

NOTE: Because of file dependencies, this hotfix requires Microsoft Windows NT 4.0
Service Pack 6a.



STATUS
======

Microsoft has confirmed that this is a problem in the Microsoft products that
are listed at the beginning of this article.

Additional query words:

======================================================================
Keywords          : kbWinNT400nospFix 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400sp6 kbWinNTS400search kbWinNTS400 kbWinNTSEnt400SP6a
Version           : :4.0,4.0 SP6a
Hardware          : ALPHA x86
Issue type        : kbbug
Solution Type     : kbfix

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