XL97: "Bad DLL Calling Convention" When Running a Macro

ID: Q158905


The information in this article applies to:
  • Microsoft Excel 97 for Windows


SYMPTOMS

When you run a Visual Basic for Applications macro in Microsoft Excel 97, you may receive the following error message:

Run-time error '49':
Bad DLL calling convention


CAUSE

This problem may occur when all of the following conditions are true:

  • The Visual Basic macro code contains one or more Declare Function statements.

    -and-


  • One of the Declare Function statements refers to a function in a dynamic-link library file (DLL) that uses the _cdecl calling convention.

    -and-


  • Within the code, you make a call to the declared function.


In Microsoft Excel 97, Visual Basic macros can only call functions that use the _stdcall calling convention. Functions that use the _cdecl calling convention are not supported.


MORE INFORMATION

DLLs in Microsoft Windows support two main calling conventions: _cdecl and _stdcall. Most 32-bit DLLs that are included with Microsoft Windows 95 and Microsoft Windows NT support the _stdcall calling convention; the _cdecl calling convention is generally used by older DLLs.

If a DLL supports only the _cdecl calling convention, you cannot call functions in that DLL from a Visual Basic macro in Microsoft Excel 97. For example, if your code includes the following function declaration:


   Declare Function memcpy& Lib "Crtdll" (ByRef Dest&, ByVal Src&, _
       ByVal Count&) 
and then attempts to call the memcpy& function, you will receive the error message described in this article. This behavior occurs because macros in Microsoft Excel 97 cannot call functions that use the _cdecl calling convention.

NOTE: In earlier versions of Microsoft Excel, you can make calls to functions that use the _cdecl calling convention.

Additional query words: XL97

Keywords : kberrmsg kbdta KbVBA xlvbmigrate
Version : WINDOWS:97
Platform : WINDOWS
Issue type : kbprb


Last Reviewed: July 6, 1999
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