Various errors occur when you run an MFC debug application with the MFC debug DLLs of another version (190487)


The information in this article applies to:

  • The Microsoft Foundation Classes (MFC), when used with:
    • Microsoft Visual C++, 32-bit Enterprise Edition 4.2
    • Microsoft Visual C++, 32-bit Professional Edition 4.2
    • Microsoft Visual C++, 32-bit Enterprise Edition 5.0
    • Microsoft Visual C++, 32-bit Professional Edition 5.0
    • Microsoft Visual C++, 32-bit Enterprise Edition 6.0
    • Microsoft Visual C++, 32-bit Professional Edition 6.0
    • Microsoft Visual C++, 32-bit Learning Edition 6.0
This article was previously published under Q190487

SYMPTOMS

Various errors or asserts can occur when you attempt to run a debug version of an MFC application with the MFC debug DLLs of another version. Possible errors include:
  • Ordinal could not be found.
    Access violation.
This occurs if you attempt to debug an MFC application built with Visual C++ 5.0 in Visual C++ 6.0 and vice versa. This can also occur if you run your MFC debug application on a machine that does not have the corresponding debug DLLs installed.

CAUSE

Debug versions of MFC are not binary compatible with previous versions. However, this problem does not occur with release builds because they are binary compatible between versions.

RESOLUTION

To debug an MFC project built with Visual C++ 5.0 in Visual C++ 6.0, you must rebuild the project. To run a debug version of an MFC project on a machine that does not have Visual C++ installed, make sure the proper version of the MFC debug DLLs are installed. Note that redistribution of MFC debug DLLs is a violation of the Visual C++ license agreement.

STATUS

This behavior is by design.

MORE INFORMATION

Steps to reproduce the behavior

  1. Build a DEBUG Build MFC application with Visual C++ 5.0.
  2. Copy the .exe file to a machine with Visual C++ 6.0 installed.
  3. Run the .exe file.

    RESULT: Runtime errors such as:
    The ordinal 3255 could not be located in the dynamic link library
    MFCO42D.DLL

    -or-

    Unhandled exception in thisisatest.exe: 0xC0000005: Access Violation.
(c) Microsoft Corporation 1998, All Rights Reserved. Contributions by Mike Francis, Microsoft Corporation.
Modification Type:MajorLast Reviewed:9/1/2005
Keywords:kbtshoot kbBug kbDebug kbDLL kbprb KB190487 kbAudDeveloper
©2004 Microsoft Corporation. All rights reserved.