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Q149639: PRB: Network DDE Requests Fail from Visual FoxPro

Article: Q149639
Product(s): Microsoft FoxPro
Version(s): WINDOWS: 3.0,3.0b,5.0,5.0a,6.0
Operating System(s): 
Keyword(s): 
Last Modified: 21-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0 
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SYMPTOMS
========

From Visual FoxPro, you can use Network DDE to make a connection to a dynamic
data exchange (DDE) enabled application over the network, but all requests are
ignored by the application. The conversation cannot be terminated.

CAUSE
=====

Visual FoxPro DDE commands are designed to talk only to local DDE servers, not
DDE servers located over a network.

STATUS
======

This behavior is by design.

WORKAROUND
==========

Use Network DDE by way of Windows API calls, such as DDEInitiate.

MORE INFORMATION
================

The following example requires use of Chat which is located in the Network group
in Windows for Workgroups.

Steps to Reproduce Behavior
---------------------------

The following example tries to start a Network DDE conversation with Winchat,
which is located on a remote computer. Before starting the conversation, load
Winchat on both client and server computers to enable NetDDE. On the client
computer, close down Winchat. On the server computer, minimize Winchat. Starting
a Network DDE conversation in Visual Basic 4.0 Enterprise Edition will 'ring'
the WINCHAT phone.

1. In the Visual FoxPro Command window, type:

        nsyschan=DdeInitiate("\\server\ndde$\chat$","chat")

  The command is accepted and returns a positive channel number but the WINCHAT
  phone doesn't ring.

2. In the Command window, type:

        ltermchan=DdeTerminate(nsyschan)

  The command returns false (.F.), and you cannot close the channel.

Additional query words: VfoxWin kbvfp300 kbvfp500a kbvfp500 kbvfp600

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS: 3.0,3.0b,5.0,5.0a,6.0

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