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Q221088: PRB: Loading COM DLL from ASP Stops IIS if FoxUser is Corrupted

Article: Q221088
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): kbAppSetup kbCOMt kbInternet kbOOP kbvfp600 kbGrpDSFox
Last Modified: 09-JUN-1999

-------------------------------------------------------------------------------
The information in this article applies to:

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

Loading an ASP that calls a Visual FoxPro COM DLL stops the FTP Publishing
Service and the World Wide Web Publishing Service (WWW) on the Windows NT Server
that is running Internet Information Server (IIS).

CAUSE
=====

This is known to happen if the FoxUser.dbf resource file that the Visual FoxPro
runtime that the COM DLL is using is corrupted.

RESOLUTION
==========

There are at least two resolutions to this:

- Delete the corrupted FoxUser file. The Visual FoxPro runtime will recreate
  one. Alternately, a valid FoxUser resource file can be provided.

- Add a Config.fpw file as an included file in the project when building the
  COM DLL. This Config.fpw file should contain the RESOURCE=OFF command. This
  will prevent the COM DLL from trying to use a resource file.

Please note that in Visual Studio 6.0 SP3 for Visual FoxPro, the FoxUser file is
no longer created or loaded by the runtime when loading a COM DLL.

STATUS
======

This behavior is by design.

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

The resource file is a Visual FoxPro table that contains information on system
and user-defined resources such as keyboard macros, preferences, system window
locations and sizes, diary entries, and so on. By default, it is named
FoxUser.dbf.

The SET RESOURCE TO <filename> command can be used within Visual FoxPro or
a Visual FoxPro runtime to set the resource file to the desired file. The
SYS(2005) function can be used to determine the name and location of the
resource file. The SET("Resource") command can be used to determine if the
resource file is being used. SYS(2005) will still report the name and location
of the resource file even if it is not currently being used.

Trying to load a Visual FoxPro COM DLL that uses a runtime that tries to use a
corrupted resource file will generate the following error messages in Visual
FoxPro and Visual Basic or Visual Basic for Applications:

In a Visual FoxPro runtime exe (with RESOURCE=OFF in its Config.fpw):

  OLE error code 0x80040154: Class not registered

In Visual Basic or Visual Basic for Applications:

  Run-time Error '429'
  ActiveX component can't create object.

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

1. Obtain the following Microsoft Knowledge Base article:

  Q168053 HOWTO: Use VFP Automation Servers with Active Server Pages

2. Implement it on Internet Information Server(IIS) so that it functions
  properly.

3. Find the FoxUser.dbf file that the Visual FoxPro runtime is using. A good
  place to look is in the \Winnt\System32 directory on the Windows NT Server.
  To facilitate determining the FoxUser file being used by the runtime, the
  following code can be added to the Visual FoxPro code in the article after
  the other two procedures but before the ENDDEFINE:

  	PROCEDURE getresource
  		x=SYS(2005)
  		IF !EMPTY(x)
  			RETURN x+" and it is "+SET("Resource")
  		ELSE
  			RETURN "There is no resource file"
  		ENDIF
  	ENDPROC

4. Rebuild the COM DLL and replace the ASPSrv.dll, ASPSrv.vbr, and ASPSrv.tlb on
  the NT Server. Then the following lines of code can be added to the Active
  Server Page, right above the </BODY> tag:

  <P>
  The Resource File info is: <%VFPSrv.GetResource()%>
  <P>

5. Load the ASP after these modifications and it will report the FoxUser file
  being used.

6. Corrupt the FoxUser that the Visual FoxPro runtime is using. An easy way to
  do this is to open FoxUser.dbf in Notepad and delete the first couple of
  lines in it. Note that the FTP Publishing and WWW Publishing services on the
  NT Server may need to be stopped to allow access to the FoxUser file. Be sure
  to restart them after corrupting the FoxUser file.

7. Open the Services control panel on the Windows NT Server. Locate the World
  Wide Web Publishing Service. Note that is should currently be Started.

8. Reload the ASP and then check the WWW Publishing Service in the Services
  control panel. It should now be Stopped. The Services control panel may need
  closed and reopened to refresh. Internet Explorer should also report the
  following:

  Internet Explorer cannot open the Internet site
  http://yourserver/VFPSrv.ASP.
  A connection with the server could not be established

REFERENCES
==========

For additional information about use Visual FoxPro COM DLLs with Active Server
Pages, please see the following article in the Microsoft Knowledge Base:

  Q168053 HOWTO: Use VFP Automation Servers with Active Server Pages

Additional query words:

======================================================================
Keywords          : kbAppSetup kbCOMt kbInternet kbOOP kbvfp600 kbGrpDSFox 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbprb

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