Q165245: DDE Client Experiences Intermittent DDE Disconnects

Article: Q165245
Product(s): Microsoft Windows NT
Version(s): winnt:4.0
Operating System(s): 
Keyword(s): kbnetworkkbbuglist kbfixlist
Last Modified: 10-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 4.0 
- Microsoft Windows NT Server version 4.0 
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SYMPTOMS
========

A DDE client application may experience intermittent DDE disconnect problems.

CAUSE
=====

XTYP_DISCONNECT message is sent by DDEML to the client application under the
following scenario:

1. Server is generating frequent calls to DdePostAdvise() on a single data item.

2. Client is making frequent requests to advise/unadvise on the same item.

The client transactions must be of type

  XTYP_ADVSTART | XTYPF_ADVREQ and XTYP_ADVSTOP.
  (Hot links of type XTYP_ADVSTART do not exhibit this problem.)

Under these circumstances, when a data packet is generated by the server after
DDEML is notified by the client of a request to unadvise but prior to the
generation of the ACK for this unadvise, DDEML sends a message of type
XTYP_DISCONNECT to the client.

STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Windows NT version
4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S.
Service Pack. For information on obtaining the service pack, query on the
following word in the Microsoft Knowledge Base (without the spaces):

  S E R V P A C K


Additional query words: 4.00 prodnt

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Keywords          : kbnetwork kbbuglist kbfixlist
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0
Issue type        : kbbug

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