Путь к базе данных

program OM;
uses
 System, SysUtils,Messages,WinProcs,
  Forms,
  Unit_DM in 'Unit_DM.pas' {DM: TDataModule},
  Unit_Main in 'Unit_Main.pas' {Form_Main};
 
{$R *.res}
 
var hnd:THandle;
ss:string;
begin
   ss:=ExtractFileName(paramstr(0) );
   hnd:=CreateMutex(nil, false, PChar(ss) );
   if GetLastError = ERROR_ALREADY_EXISTS then
   begin
      Beep(100,200); //MessageBeep ->in WinProcs
      ReleaseMutex(hnd);
      Exit;
   end;
   Application.Initialize;
   Application.CreateForm(TDM, DM);
   if DM.ConnectionError = true then
   begin
      DM.Free;
      DM:=nil;
      ReleaseMutex(hnd);
      Exit;
   end;
   Application.CreateForm(TForm_Main, Form_Main);
   Application.Run;
end.

unit Unit_DM;
interface
uses
  Windows,SysUtils, Classes, DB, ADODB,Variants,dialogs,Messages;
type
  TDM = class(TDataModule)
    ADOConnection1: TADOConnection;
    ...
 
    procedure DataModuleCreate(Sender: TObject);
  private
   FConnectionError: boolean;
    { Private declarations }
  public
    property ConnectionError: boolean read FConnectionError;
    { Public declarations }
  end;
var
  DM: TDM;
  path:string;
 
implementation
 
{$R *.dfm}
 
 
begin
  Try
     GetDir(0,path); 
     ADOConnection1.Close;
     ADOConnection1.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+path+'\Tables\OM.mdb;Persist Security Info=False';
     ADOConnection1.Open;
     MainTable.Open;
 
  Except
     on E: Exception do
     begin
        FConnectionError := True;
        ADOConnection1.Close;
        MainTable.Close;
        ShowMessage('Ошибка соединения!');
     end
   End;
end;