Q105289: SMTP: Gateway Hangs Using Novell LAN Workplace for DOS

Article: Q105289
Product(s): Microsoft Mail For PC Networks
Version(s): MS-DOS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 05-NOV-1999

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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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