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Q191636: FIX: Access Violation or Page Fault with Multiple Toolbars

Article: Q191636
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0,3.0b,5.0,5.0a
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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

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

SYMPTOMS
========

When running code that instantiates, docks, and releases multiple toolbars, you
may see an error similar to the following under Windows NT:

  Exception: access violation (0xc0000005), Address: 0x77f7d514

The following error occurs under Windows 95:

  VFP caused an invalid page fault in module KERNEL32.DLL at 0137:bff78053

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug has been corrected in Visual FoxPro 6.0.

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

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

1. Run the following code from a program (.prg) file:

        #DEFINE    ARRAYSIZE       14
        DIMENSION oRef[ARRAYSIZE]
        FOR lni = 1 TO ARRAYSIZE
           oRef[lni] = CREATEOBJECT("Toolbar")
           oRef[lni].SHOW
           oRef[lni].DOCK(1)
           WAIT WINDOW "Creating "+ STR(lni) NOWA
        ENDFOR
        WAIT CLEAR
        FOR lni = 1 TO ARRAYSIZE
           WAIT WINDOW "Releasing "+ STR(lni) NOWA
           oRef[lni] = .NULL. && Use this in VFP 5, 3.0b
        ENDFOR
        WAIT CLEAR

2. Under Windows NT, you see an error like the following:

  Exception: access violation (0xc0000005), Address: 0x77f7d514

  Under Windows 95, you will see an error like the following:

  VFP caused an invalid page fault in module KERNEL32.DLL at 0137:bff78053

NOTE: It may take multiple runs of the preceding program before you see the error
occur in Windows 95.

REFERENCES
==========

(c) Microsoft Corporation 1998, All Rights Reserved.
Contributions by Jim Saunders, Microsoft Corporation


Additional query words: kbVFp300bbug kbVFp500abug kbVFp600fix kbXBase kbfvp600fix

======================================================================
Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP500a
Version           : WINDOWS:3.0,3.0b,5.0,5.0a
Issue type        : kbbug
Solution Type     : kbfix

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