Hi
We have a isapi filter for our website write in c++ version 6 we receive sometime an error message at runtime "R6025 pure virtual function call"

Below is the code we use. If someone have any idea how to correct the problem this will help us

Thanks

#include <afx.h>
#include <stdio.h>
#include <stdlib.h>
#include <httpfilt.h>

#import "d:\systemes\applic\sitebssfd\sitebssfd.tlb"	// Définition du DLL Fox
//#import "D:\temp\test.tlb"	// Définition du DLL Fox


// définition du type AUTH_COMPLETE 
#define SF_NOTIFY_AUTH_COMPLETE             0x04000000

typedef struct _HTTP_FILTER_AUTH_COMPLETE_INFO
{
   BOOL (WINAPI * GetHeader) (
      struct _HTTP_FILTER_CONTEXT * pfc,
      LPSTR lpszName,
      LPVOID lpvBuffer,
      LPDWORD lpdwSize
      );
   BOOL (WINAPI * SetHeader) (
      struct _HTTP_FILTER_CONTEXT * pfc,
      LPSTR lpszName,
      LPSTR lpszValue
      );
   BOOL (WINAPI * AddHeader) (
      struct _HTTP_FILTER_CONTEXT * pfc,
      LPSTR lpszName,
      LPSTR lpszValue
      );
   BOOL (WINAPI * GetUserToken) (
      struct _HTTP_FILTER_CONTEXT * pfc,
      HANDLE * phToken
      );
   DWORD HttpStatus; 
   BOOL  fResetAuth; 
   DWORD dwReserved; 
} HTTP_FILTER_AUTH_COMPLETE_INFO, *PHTTP_FILTER_AUTH_COMPLETE_INFO;


BOOL WINAPI __stdcall GetFilterVersion(HTTP_FILTER_VERSION * pVer)
{
    pVer->dwFlags = (SF_NOTIFY_NONSECURE_PORT | SF_NOTIFY_AUTH_COMPLETE | SF_NOTIFY_ORDER_DEFAULT); //  Spécifier le type de notification

    pVer->dwFilterVersion = HTTP_FILTER_REVISION;  //Version interne du filter

    strcpy( pVer->lpszFilterDesc, "Filtre Bssfd 1.0"); //Version dans la propriété

    return TRUE;
}

DWORD WINAPI __stdcall HttpFilterProc(HTTP_FILTER_CONTEXT * pfc, DWORD NotificationType,VOID * pvData)
{
	char cUserName[33]; // Usager
	char cUrl[512]; // Url
	DWORD wLongUser = sizeof(cUserName); // Longueur du buffer
	DWORD wLongUrl = sizeof(cUrl); // Longueur du buffer

	_variant_t vUrl,vUserName,vUrlRetour;	// declare variant variables.
	_bstr_t res;

	PHTTP_FILTER_AUTH_COMPLETE_INFO pFACI;
  

	using namespace sitebssfd;	//use the PostSetup namespace
	IcommunPtr psetup;    // declare a smart ptr to the server

	switch ( NotificationType )
    {

		case SF_NOTIFY_AUTH_COMPLETE:
			pFACI = (PHTTP_FILTER_AUTH_COMPLETE_INFO)pvData;

			pFACI->GetHeader(pfc, "url", cUrl, &wLongUrl); // Lecture de l'URL
			pfc->GetServerVariable(pfc,"LOGON_USER", cUserName,  &wLongUser);  //Lecture de l'usager

			vUrl = cUrl;  // Tranformer l'URL en variant pour le passer à fox
			vUserName = cUserName; // Tranformer l'usager en variant pour le passer à fox

			CoInitialize(0);			// initialize COM
			psetup.CreateInstance("sitebssfd.commun");	//create an instance
			vUrlRetour = psetup->verifieaccespage(&vUserName,&vUrl);  // Appel de la fonction Fox
			psetup->detruireobj();
			psetup = 0;				// release the server
			CoUninitialize();		//uninitialize COM

			res = vUrlRetour.bstrVal;
			pFACI->SetHeader(pfc, "url", res); // Écriture de l'URL

			break;  
             
		default:
			break;        
    }

    return SF_STATUS_REQ_NEXT_NOTIFICATION;
}