en este cogigo agrega un print
Cita: <?
session_start();
//ver que la variable aparece en pantalla
echo $carpeta= $_SESSION['carpeta'];
$uploaddir=$carpeta.'/';
$file = $uploaddir . basename($_FILES['uploadfile']['name']);
if (move_uploaded_file($_FILES['uploadfile']['tmp_name'], $file)) {
echo "success";
} else {
echo "error ".$_FILES['uploadfile']['error']." --- ".$_FILES['uploadfile']['tmp_name']." %%% ".$file."($size)";
}
?>