me explico en localhost funciona bien el problema surge al subirlo a algun host aparece lo siguiente
Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /storage/ssd3/893/822893/public_html/index.php:33) in /storage/ssd3/893/822893/public_html/php/login.php on line 16
Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /storage/ssd3/893/822893/public_html/index.php:33) in /storage/ssd3/893/822893/public_html/php/login.php on line 16
Warning: Cannot modify header information - headers already sent by (output started at /storage/ssd3/893/822893/public_html/index.php:33) in /storage/ssd3/893/822893/public_html/php/login.php on line 20
este es mi login
<?php
$correo=$_POST['correo'];
$clave=md5($_POST['clave']);
require_once('Conexion.php');
$conn = Conectar();
$stmt = $conn->prepare("SELECT id_usuario, nombre, apellido, correo, p.id_perfil, perfil FROM usuario u INNER JOIN perfil p ON p.id_perfil=u.id_perfil WHERE u.correo=:correo AND u.clave=:clave");
$stmt->bindParam(':correo',$correo);
$stmt->bindParam(':clave',$clave);
$stmt->execute();
if($stmt->rowCount()==1){
session_start();
$fila=$stmt->fetch();
$_SESSION['idperfil']=$fila['id_perfil'];
if($fila['id_perfil']==1)
{header("Location: administrador/index.php");}
if($fila['id_perfil']==2)
{header("Location: aprendiz/index.php");}
if($fila['id_perfil']==3)
{header("Location: root/index.php");}
}
else{
echo "<font color='red'>Datos No Validos</font>";
}
?> el index
<!DOCTYPE html>
<html lang="es">
<head>
<link href="/css/bootstrap.css" rel="stylesheet">
<meta charset="UTF-8">
<title>Inicio de sesion</title>
</head>
<body background="img/texture.jpg">
<div class="groupLogin">
<form action="" method="POST">
<label><font color="red">Correo</font></label>
<input type="email" name="correo" placeholder="Ingrese Correo" required="">
<br>
<label><font color="red">Clave</font></label>
<input type="password" name="clave" placeholder="Ingrese Clave" required="">
<br>
<center>
<input type="submit" value="Ingresar">
</center>
</form>
<div>
<?php
if(isset($_POST['correo'])&&isset($_POST['clave'])){
require_once "php/Conexion.php";
require_once "php/login.php";
}
?>
</body>
</html>
<footer>
<?php
include('footer.php');
?>
</footer>seguridad
<?php
session_start();
if(!isset($_SESSION['idperfil'])){
header("Location: ../index.php");
}cerrar sesion
<?php
require_once('php/Conexion.php');
session_start();
session_unset();
session_destroy();
header("Location: index.php");
no se donde esta el error yo veo todo normal habia visto por hay que el session_start debe estar al inicio del codigo despues de la etiqueta de php pero lo puse hay y sigue igual y no se que nmas sera
