_CtrIsValidHeapPointer(pUserData) problem

can you upload the code in which you create the connection and the code for closing it?

The code I am using just as follows:
Thanks




#include <stdio.h>
#include <afxdisp.h>
#import "c:\program files\common files\system\ado\msado15.dll" rename ("EOF","adoEOF") no_namespace

#define CREATEiNSTANCE(sp,riid) { HRESULT _hr =sp .CreateInstance( __uuidof( riid ) ); \
                                 if (FAILED(_hr)) _com_issue_error(_hr); }

#define RsITEM(rs,x) rs->Fields->Item[_variant_t(x)]->Value
#define UC (char *)
struct InitOle {
   InitOle()  { ::CoInitialize(NULL); }
   ~InitOle() { ::CoUninitialize();   }
} _init_InitOle_;       // Global Instance to force load/unload of OLE

void main(){
   _RecordsetPtr   spRS;
   _ConnectionPtr  spCON;
   try{
       CREATEiNSTANCE(spCON,Connection);
       spCON->ConnectionString = L"driver={sql server};SERVER=(local);Database=pubs;UID=sa; PWD=;";
       // spCON->ConnectionString =L"DRIVER={Microsoft Access Driver (*.mdb)};DBQ=authors.MDB;DefaultDir=C:\\test;";
           
       spCON->Open( "", "", "", -1 );
       CREATEiNSTANCE(spRS,Recordset)
       spRS->PutRefActiveConnection( spCON );
       spRS->Open("select au_lname, au_fname from authors",
              vtMissing, adOpenKeyset,
           adLockBatchOptimistic, -1
         );
       while(spRS->adoEOF == false){
           printf("au_lname = %s  au_fname = %s \n",
                   UC _bstr_t(RsITEM(spRS,0L)),
                   UC _bstr_t(RsITEM(spRS,"au_fname"))
              );
           spRS->MoveNext();
       }
       spRS->Close();
       spCON->Close();
   }
   catch( _com_error &e){
       _bstr_t bstrSource(e.Source());
       _bstr_t bs =  _bstr_t(" Error: ") + _bstr_t(e.Error()) + _bstr_t(" Msg: ")
           + _bstr_t(e.ErrorMessage()) + _bstr_t(" Description: ")
           + _bstr_t(e.Description());
       
       MessageBox(0,bs,bstrSource, MB_OK);
   }          
}

look at this page:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vccore98/html/_crt__crtisvalidheappointer.asp

debug your application, and when it's sopt on that line, go back on the stack to see the command and pointer which cause the problem.