EasyPHP, why doesn't file upload work?

Question

PHP

There is a plugin for jQuery.
I installed it, everything works except one. Save to folder. From the HTML
page : jQuery Script :
<div id="fileuploader">Upload</div>

$("#fileuploader").uploadFile({
        url: "../php/foto_upload.php",
        fileName: "myfile",
        showProgress: true,
        showPreview: true,
        autoDone: true,
        showDelete: true,
        showDownload: true,
        previewHeight: "15%",
        previewWidth: "15%"
});

On the PHP server side :

<?php
<?php

$output_dir = "../tmp/";

if (isset($_FILES["myfile"])) {
    $ret = array();
    //This is for custom errors;	
//    $custom_error = array();
//    $custom_error['jquery_upload_file_error'] = "File already exists";
//    echo json_encode($custom_error);
//    die();
    $error = $_FILES["myfile"]["error"];
    //You need to handle  both cases
    //If Any browser does not support serializing of multiple files using FormData() 
    if (!is_array($_FILES["myfile"]["name"])) { //single file
        $fileName = $_FILES["myfile"]["name"];
        move_uploaded_file($_FILES["myfile"]["tmp_name"], $output_dir . $fileName);
        $ret[] = $fileName;
    } else {  //Multiple files, file[]
        $fileCount = count($_FILES["myfile"]["name"]);
        for ($i = 0; $i < $fileCount; $i++) {
            $fileName = $_FILES["myfile"]["name"][$i];
            move_uploaded_file($_FILES["myfile"]["tmp_name"][$i], $output_dir . $fileName);
            $ret[] = $fileName;
        }
    }
    echo json_encode($ret);
}

And $fileName returns. That is, the error is only in move_uploaded_file or $output_dir .

EasyPHP installed on Win10 1607 15048.0, run as admin. Where is the mistake?