// TRHEAD funktionen
UINT CControl::ThreadFunc(LPVOID Data){

    threadPara *back = (threadPara*)Data;

	CStatic *p = (CStatic*) back->pInstance->GetDlgItem(IDC_STATIC);

	CString str="Thread Iteration: ";
	int i=0;
	while(back->pInstance->EndThread){

		str.Format("%i",i++);
		p->SetWindowText(str);
	}

//	::PostMessage((HWND)Data, WM_THREADFINISHED, 0, 0);

	//AfxEndThread(false);
	return 0;
} 

void CControl::startThread(){

	param->a=0;
	param->b='a';
	param->pInstance=this;
	int i=0;
	index=&i;

	EndThread=true;
	if(pThread==NULL)
		pThread= AfxBeginThread(CControl::ThreadFunc,(LPVOID)param);
	//hThread= CreateThread( NULL,0,CControl::ThreadFunc,(LPVOID)param,0,&dwThread); 

}

// Dilaog schliessen

void CControl::OnBnClickedCancel(){

	DWORD status;

	EndThread=false;
	::GetExitCodeThread(pThread->m_hThread,&status);
	if(status == STILL_ACTIVE)
	      MessageBox("Thread In Execution");

         pThread=NULL;

	OnCancel();
}

wenn das dilaog geschlossen wurde kommt fehler in dbgheap.h