Sending the header is not something I know how to do.
But you did give me an idea that fixed all my problems! I had to think of what was in the 'head' or top of all the pages...:
I had a 'log' script that I was using, placed on the index.php page - when I removed this, everything started working again (cookies, searches, attachments).
<?php
$time = date("l, F jS Y - g:ia");
$ip = getenv("REMOTE_ADDR");
$referer = getenv("HTTP_REFERER");
$browser = getenv("HTTP_USER_AGENT");
$hoter = getenv("REMOTE_HOST");
$fp = fopen("logs.html", "a+");
fputs($fp, "
<i style=color:ff0;>MAIN SITE</i><br />
<b>Time:</b> $time<br />
<b>IP Address:</b> $ip<br />
<b>Referer URL:</b> <a target=_blank href=$referer>$referer</a><br/>
<b>Browser Type:</b> $browser<hr noshade size=1 />");
fclose($fp); ?>
So, I guess no tracker script for me, but I rather have my site running correctly anyway. 😃
Thank you for your help!!!