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Q215362: HOWTO: Detect DCOM Installation Under VFP 6.0

Article: Q215362
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): kbDCOM kbOSWinNT400 kbvfp600 kbOSWin95 kbOSWin98 kbFFC
Last Modified: 04-FEB-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 6.0 
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SUMMARY
=======

This article illustrates how to detect whether DCOM is installed in a Windows
95/98 or a Windows NT 4.0 machine from within Visual FoxPro 6.0.

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

An application created with a Top-Level form needs DCOM installed in order to
work properly when the Visual FoxPro main desktop is suppressed in the
Config.fpw with SCREEN=OFF.

With the code below, you can detect that DCOM is present. Based on this
information, you can shut down the application if necessary.

  #DEFINE HKEY_LOCAL_MACHINE  -2147483646
  #DEFINE DCOMKEYSTRING 'SOFTWARE\Microsoft\OLE'
  #DEFINE ENABLEDCOMKEY 'EnableDCOM'

  SET CLASSLIB TO HOME()+"ffc/REGISTRY.VCX"
  oReg=CREATEOBJECT('registry')
  LOCAL lFoundDCOM
  lFoundDCOM = .F.
  IF oReg.OpenKey(DCOMKEYSTRING,HKEY_LOCAL_MACHINE,.F.) = 0
     LOCAL cValue
     cValue = ''
     IF oReg.GetKeyValue(ENABLEDCOMKEY,@cValue) = 0
        lFoundDCOM = !EMPTY(cValue)
     ENDIF
  ENDIF
  IF !lFoundDCOM
     MESSAGEBOX('DCOM not install on system')
  ELSE
     MESSAGEBOX('DCOM install on system')
  ENDIF

REFERENCES
==========

For additional information about exception errors terminating Top-Level form in
Visual FoxPro applications, please see the following article in the Microsoft
Knowledge Base:

Q193472 BUG: Exception Error Exiting Top-Level Form App in Windows 95

Additional query words: DCOM

======================================================================
Keywords          : kbDCOM kbOSWinNT400 kbvfp600 kbOSWin95 kbOSWin98 kbFFC 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbhowto

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