DOCUMENT:Q105289  05-NOV-1999  [pcmail]
TITLE   :SMTP: Gateway Hangs Using Novell LAN Workplace for DOS
PRODUCT :Microsoft Mail For PC Networks
PROD/VER:MS-DOS:3.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Mail Gateway to SMTP, version 3.0 
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SUMMARY
=======


SYMPTOMS
========

The Microsoft Mail Gateway to SMTP may hang during message transmission when
using Novell's TCP/IP product for the PC (LAN Workplace for DOS). This error
appears:

   ERROR write: (9) Bad file number

The following lines appear in the log file as errors when you use the -CD and
-LACSY options with SMTPGATE. (NOTE: Each error appears on one on one long line
in the log file; they are broken here due to formatting restrictions.)

   [rx] 451 net hang reading from SMTP_GATEWAY_MACHINE: Connection timed out
   during HELO with SMTPSMART_HOST.

   14:34:25 - ERROR Invalid response to MAIL: 451 net hang reading from
   SMTP_GATEWAY_MACHINE: Connection timed out during HELO with
   SMTP_ROUTER/HOST_MACHINE.

CAUSE
=====

The way LAN Workplace for DOS handles IP fragmentation causes the SMTP Gateway
layer to hang because it is waiting for a good packet of information to process
and has no time-out limit for waiting.

RESOLUTION
==========

To avoid this problem, either:

 - Upgrade to the latest version of LAN Workplace for DOS and apply all the
   necessary patches.

-or-

 - Configure LAN Workplace for DOS to use the smallest packet size available:
   632. The default size is 2048.

Additional query words: 3.00 ErrMsg ERROR write: (9) Bad file number

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Keywords          :  
Technology        : kbMailSearch kbMailGateSearch kbZNotKeyword3 kbMailGateSMTP300
Version           : MS-DOS:3.0

=============================================================================

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