DOCUMENT:Q122494  15-DEC-2000  [crossnet]
TITLE   :Network Storm Caused By Basic Redirector
PRODUCT :Windows for Workgroups and Windows NT Networking Issues
PROD/VER::
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Network Client for MS-DOS version 3.0 
 - Microsoft Workgroup Add-On for MS-DOS 
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SYMPTOMS
========

Your network workstation configured with the Basic Redirector from the Microsoft
Network Client version 3.0 for MS-DOS, or from the Microsoft Workgroup Add-On
for MS-DOS version 3.11 may hang and create a network storm (excessive network
traffic that can render a network ineffective). This problem will only occur
with some applications in specific situations.

CAUSE
=====

When an application requests a read past the end of a file on a network server,
the server will respond with an indication that there is no data in the
requested range. The redirector then adjusts the request, based on the current
size of the file on the server.

In the case of an empty (zero-byte) file, there is an error in the adjustment
code of the Basic Redirector which causes the it to repeatedly make the same
network request. The sequence of network requests are a Seek, followed by a
Read, then another Seek and Read, and another, and so on.

Some commercial applications can, in some circumstances, initiate this sequence
of requests, triggering the network "storm".

WORKAROUND
==========

Use the Full Redirector, the redirector from Lan Manager version 2.2, or Windows
for Workgroups version 3.11.

STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Workgroup Add-On for
MS-DOS, Version 3.11 and Microsoft Network Client v3.0 for MS-DOS. We are
researching this problem and will post new information here in the Microsoft
Knowledge Base as it becomes available.


Additional query words: wfw wfwg prodnt 3.00 3.11

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Keywords          :  
Technology        : kbAudDeveloper kbZNotKeyword kbWFWSearch kbNetworkClientSearch kbNetworkClient300DOS
Version           : :

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