Project throws exception only in debug mode

Look at the call stack and see if you can trace back to which call (from your code, not internal MFC code) caused the exception. Usually you can trace back a bit to find where it occurred, if there isn't enough history there, try placing TRACE statements to narrow down which call is causing that, since its breaking upon reaching a wndproc, i'd suspect that one of the SendMessage() calls is causing the problem (not directly, but something that's using that call), although when using MFC, a lot of the GUI stuff also uses SendMessage() calls internally.

This is the my code. It runs completely through it and then gets into the system stuff I previously posted. I really think the reason is an odbc problem.

void CInfoFView::OnMove(UINT cmdButton) {

	unsigned int nNumRecords = m_pRs->GetNumRecords();
	if (nNumRecords==0){
		return;
	}
	switch (cmdButton){
		case IDC_MOVEPREVIOUS_INFO:
			m_pRs->MovePrev();
			if (!m_pRs->IsBOF()){
				m_ulRecordNumber--;
				if (m_ulRecordNumber==1 && m_New.IsWindowEnabled()){
					m_New.SetFocus();
					SendMessage(DM_SETDEFID,IDC_NEW_INFO);
				}
				break;
			}
			//BOF, else fall through.  Should never get here as button will be disabled
		case IDC_MOVEFIRST_INFO:
			m_pRs->MoveFirst();
			m_ulRecordNumber=1;
			if (m_New.IsWindowEnabled()){
				m_New.SetFocus();
				SendMessage(DM_SETDEFID,IDC_NEW_INFO);
			}
			break;
		case IDC_MOVENEXT_INFO:
			m_pRs->MoveNext();
			if (!m_pRs->IsEOF()){
				m_ulRecordNumber++;
				if (m_ulRecordNumber==nNumRecords && m_New.IsWindowEnabled()){
					m_New.SetFocus();
					SendMessage(DM_SETDEFID,IDC_NEW_INFO);
				}
				break;
			}
			//EOF, else fall through
		case IDC_MOVELAST_INFO:
			m_pRs->MoveLast();
			m_ulRecordNumber=nNumRecords;
			if (m_New.IsWindowEnabled()){
				m_New.SetFocus();
				SendMessage(DM_SETDEFID,IDC_NEW_INFO);
			}
			break;
	}
	DisplayCounters();
	fromRsToCtrls();
	EvaluatePosition();
	//Keeping a record of the current Linker value so other tables can use.
	m_pDoc->setLinker(m_pRs->m_Linker);
	m_pDoc->UpdateAllViews(this);

I know I'm not helping much but I'm trying. This application has been working for two years without a problem. Now that it is in Visual Studio 2008 it doesn't work in Debug mode. Release mode is fine. Here is where it blows up. After the return statement. return AfxCallWndProc(pWnd, hWnd, nMsg, wParam, lParam);

The first 3 parameters have addresses while wParam and lParam do not. The error occurs when I attempt to move to the next record. Hope that helps.

AfxWndProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam) { // special message which identifies the window as using AfxWndProc if (nMsg == WM_QUERYAFXWNDPROC) return 1; // all other messages route through message map 

CWnd* pWnd = CWnd::FromHandlePermanent(hWnd); 
ASSERT(pWnd != NULL); 
ASSERT pWnd==NULL || pWnd->m_hWnd == hWnd); 
if (pWnd == NULL || pWnd->m_hWnd != hWnd) 
     return ::DefWindowProc(hWnd, nMsg, wParam, lParam); 

return AfxCallWndProc(pWnd, hWnd, nMsg, wParam, lParam); 
}

The message saying the debugger cannot find a dbg file, is just information, not an error. Your program should run with or without it.

And "Warning: Setting forwardOnly recordset readOnly." is just a warning saying you should have set the readOnly flag in the options when using forwardOnly, and that your record set class does it for you.

Well, that leaves us with no error information at all.

I suggest you trace back to the last point in the code you have control, and start checking parameter values to all system calls you make.

There can be different reasons. By the way, you provide output, not exception. Please, provide full exception dump and show the like of code where it happens. Why forcing us into guesswork?

Anyway, there are typical common problems which cause such situation. Maybe most usual of them is the failure to find some file(s) in one of the configurations, because of incorrect assumptions on the file path. By the way, you can use the Debugger even in Release configuration. The difference is, most likely, not due to running under the debugger, but due to different project configuration, which is not the same. Run under debugger with Release configuration; and you will probably see if the file is still not found.

You should never assume any certain work directory during run-time. The working directory depends on Configuration, but in fact it is defined by the user at the moment of starting the application. You should never use absolute path or assume the path is visible due to Environment variable(s). It means you need to calculate the path to your data file during run-time. This path can be relative to your executable module (but usually only if this is immutable data) or one of the special directories, such as "All users" application data, etc.

[EDIT]
Getting to further detail of the problem needs more exception information; first of all, lines of code where it happens. As your problem is manifested under Debugger, this is not too hard: you can catch exception, put a break point where exception is caught and look for stack using Visual Studio Debug -> Windows -> Call stack. This can be enough to find our there in code it happens for the purpose of reporting it in the CodeProject Question.

Dumping it programmatically is a bit more difficult; I haven't done it in C++ (in .NET its part of standard API), but Google search shows A Simple C++ Function Call Stack Trace Utility[^], http://stackoverflow.com/questions/3355683/c-stack-trace-from-unhandled-exception[^], http://stackoverflow.com/questions/1796225/get-stack-trace-from-uncaught-exception[^].

—SA