conectou
 <form id="saldo"  name="saldo" action="?go=gravar" method="POST" enctype="multipart/form-data">

 <title>Estoque Supermercado</title>

 <h1>IMPORTAÇÃO Estoque</h1>
  <br><p>	<input type="file" name="arquivo" value="selecionar" />

<br><p>	<input type="submit" id="confirma" value="CONFIRMAR" />

</p>

</p>

       <p>

         <a href="../index.php">Pagina Principal</a>

        </p>  

 </form>

</body>

</div>

</html>