Question

what could be a problem of that, file int the server is good, but after I press download it get corrupted…

<?php
if (isset($_POST['submit'])) {
    header('Content-type: application/vnd.openxmlformats-officedocument.wordprocessingml.document');
    header('Content-Disposition: attachment; filename="ataskaita.docx"');
    readfile('../generavimui/ataskaita.docx'); 
}
?>

Answer 1

try ereasing the output buffer before reading the file

if (isset($_POST['submit'])) {
    header('Content-type: application/vnd.openxmlformats-officedocument.wordprocessingml.document');
    header('Content-Disposition: attachment; filename="ataskaita.docx"');
    ob_clean();
    flush();
    readfile('../generavimui/ataskaita.docx'); 
}