Some images don't appear.

I have this code.

    	$cont = 0;
    	while ($row = $books->fetch_array(MYSQLI_BOTH) and $cont < 5) {
    <img src="images/banners/<?php echo $row['id_book']; ?>.jpg" data-thumb="images/<?php echo $cont; ?>.jpg" alt="<?php echo $row['id_book']; ?>" />
    <?php }  ?>

On local appear 5 images but in my page only pear 3. The filename of the images that don’t appear are “BU2075.jpg and BU1032.jpg”. I don’t know if this is causing a conflict or something.

wend I try to look the holder folder were is located the file the file name appear but when I click them the page send my to the error page. 404 Page Not Found. but with other images that doesn’t happen.

here is the link of the folder