Remove blank spaces that's not visible in the code - html

Question

I have a strange blank space in top of one of my divs.
Heres the html:
<!-- ### Bottom content container ### -->
<div class="bottom_content">
<div class="messages"><!-- include problems.php - down devices -->
<?php include "problems.php";?>
</div>
</div>
<!-- ### End bottom content container ### -->
When I examine the output I notice there are two ""after the comment inside the messagesclass. Like this:
<div class="messages"><!-- include problems.php - down devices -->
" "
<?php include "problems.php";?>
</div>
Heres the messages css:
.messages {
display:block;
width: auto;
padding: 10px;
padding-top: -10px; /* Added this to try to remove blank space in top of div */
background: rgb(255, 255, 255); /* The Fallback */
background: rgba(255, 255, 255, 0.5);
-moz-border-radius: 10px;
border-radius: 10px;
border: #ffffff 1px solid;
}
This creates a blank line in top of the div. How can I remove this? I can't find the these two "" anywhere in the code, nor can I find any blank spaces.
EDIT:
Here's the problems.php:
<center><div id="chkerror"></div></center>
This is autofilled with content from a separate php file every 30 seconds using the following jquery:
// <![CDATA[
$(document).ready(function() {
$.ajaxSetup({ cache: false }); // This part addresses an IE bug. without it, IE will only load the first number and will never refresh
setInterval(function() {
$('#chkerror').load('chkIncludes.php');
}, 30000); // the "30000" here refers to the time to refresh the div. it is in milliseconds.
});
// ]]>
And heres the content of chkIncludes.php:
<?php include "chkLoc1.php";?>
<?php include "chkLoc2.php";?>
chkLoc1.php and chkLoc2.php contains :
<?php
$host = "10.10.10.1";
$loc = ("Location 1");
$output = array();
exec("ping -n 1 $host 2>&1", $output);
//you can use print_r($output) to view the output result
if (count($output) > 7) {
$output = null;
$status = ("up");
$formattedstatus = ("<font color='green'><b>$status</b></font>");
}
else {
$output = null;
$status = ("down");
$formattedstatus = ("<font color='red'><b>$status</b></font>");
};
echo ("<div class='$status'><a href='#18/58.99940/5.62324' class='locLink' title='Click to show'><b>$loc</b> <i>(IP: $host)</i> is $formattedstatus</a></div>");
?>

Answer 1

Make sure that problems.php file is encoded without BOM (Byte order mark).
If you're using Notepad++, you can achieve that through:
Encoding > Encode in UTF-8 without BOM