Ошибка при сохранении документа из TMemo

if(OpenDlg->Execute())
  {
    Memo->Lines->LoadFromFile(OpenDlg->FileName);
  }
  Memo->Lines->SaveToFile("C:\\File\\data.txt");

TList *L;
//---------------------------------------------------------------------------
__fastcall TFEditor::TFEditor(TComponent* Owner)
    : TForm(Owner)
{
L= new TList;
}
//---------------------------------------------------------------------------
void __fastcall TFEditor::AcOpenFileExecute(TObject *Sender)
{
if(OpenDialog1->Execute())
 {
 TStringList *SL= new TStringList;
 SL->LoadFromFile(OpenDialog1->FileName);
 
 TabControl1->TabIndex=TabControl1->Tabs->Add(ExtractFileName(OpenDialog1->FileName));
 L->Add(SL);
 
 Caption= TabControl1->Tabs->Strings[TabControl1->TabIndex]+" - Editor";
 
 Memo1->Lines->Assign(SL);
 }
}
//---------------------------------------------------------------------------
void __fastcall TFEditor::AcChangeTabExecute(TObject *Sender)
{
TStringList *SL= (TStringList*)L->Items[TabControl1->TabIndex];
Memo1->Lines->Assign(SL);
 
Caption= TabControl1->Tabs->Strings[TabControl1->TabIndex]+" - Editor";
}
//---------------------------------------------------------------------------
void __fastcall TFEditor::FormDestroy(TObject *Sender)
{
for(int i=0;i<L->Count;i++) delete L->Items[i];
delete L;
}
//---------------------------------------------------------------------------

if(Memo1->Modified)
 {
 ((TStringsList*)L->Items[old_index])->Assign(Memo1->Lines);
 Memo1->Lines->SaveToFile("temp_file_N34.txt");
 }