Bez tego w miejscu polskich znaków mam tzw. "krzaki", natomiast po dodaniu utf8_decode w miejscu polskich znaków pojawiają się znaki zapytania.

<?php //Import PHPMailer classes into the global namespace //These must be at the top of your script, not inside a function use PHPMailer\PHPMailer\PHPMailer; use PHPMailer\PHPMailer\SMTP; use PHPMailer\PHPMailer\Exception; //Load Composer's autoloader require 'autoload.php'; //Create an instance; passing `true` enables exceptions $mail = new PHPMailer(true); $mail->addCustomHeader('Content-Type', 'text/plain;charset=utf-8'); $mail->Encoding = 'base64'; $honeypot = $_POST['honey']; $user_name = utf8_decode($_POST['name']); $user_email = $_POST['email']; $user_message = $_POST['message']; $user_phone = $_POST['phone']; $max_size = 2 * 1024 * 1204; //2mb $attachment = $_FILES['uploaded-file']; if ($_SERVER["REQUEST_METHOD"] == "POST") { exit; } else { $mail = new PHPMailer; //From email address and name $mail->isMail(); //sender $mail->From = $user_email; $mail->FromName = $user_name; //recipient $mail->addAddress("jaroslaw.mor@gmail.com"); //mail subject $mail->Subject = "Zapytanie ze strony www"; $mail->isHTML(true); //body mail $mail->Body = "Telefon:$user_phone<br><br>Treść wiadomośći:<br>$user_message"; $mail->AltBody = "Telefon:$user_phone\n$content"; //attachment if ($_FILES['uploaded-file']['error'][$i] !== UPLOAD_ERR_OK) continue; $file_TmpName = $_FILES['uploaded-file']["tmp_name"][$i]; $file_name = utf8_decode( $_FILES['uploaded-file']["name"][$i]); if ($_FILES['uploaded-file']['size'][$i] > $max_size) { } else{ $mail-> AddAttachment("uploads/". $file_name); } }//for }//isset if(!$mail->send()) { } else { }//if send else }//honey else end }//post end