OK I'm searching for a coding error, like a missing closing tag to a div
which I now see in the previous image, but I can't find it ???

Part of the reason I can't find the error as it isn't there until I try and download and I can't see yet how the header is modified to remove the topic title etc.

Giving myself a head ache trying to sort this non stop for hours.
Please got to http://rogerlovejoy.net/blog/b2evo.php/math-terms and let me know what you think of the problem.

Any ideas will be appreciated :(

The <header> Tag overwrites the post title and everything until [skin_include( '_item_content.inc.php']

UPDATE
I have tried changing skins but I either get the same result (evopress) or the links don't show (Manual, Colourise and Pixel skin)
Will now delete my various style.css etc.

OK I'm getting somewhere. After deleting the style.css in the [/media/***] I get exactly the same problem with (Evopress) and no links with the others as mentioned. I get the same error

<header>
	<div class="evo_post_title"</div>
		<h1>Download: mathterms.css</h1>
	</div>

OK Think I've found the error in [/skins_fallback_v5/download.disp.php] in version 6.10.2

<header>
	<div class="evo_post_title"</div>
		<h1>Download: <?php echo $download_File->get_name(); ?></h1>
	</div>
</header>

Note the missing closing &gt; after the class="evo_post_title"

Will correct and see if that solves the problem
EDIT 1
Oh dear. It has an effect but it is more of a mess so will have to check it all out from scratch

EDIT 2
Next step was to remove the closing </div> which is better.

<header>
	<div class="evo_post_title">
		<h1>Download: <?php echo $download_File->get_name(); ?></h1>
	</div>
</header>

I no longer get an html error as in the beginning of the post but the code block still overwrites the post title and won't go away.

We'll check.

Ok Thanks

Meanwhile I have completely messed with [_download.disp.php] and moved to my skin folder, so I just get the browser pop-up and keep my post as is with just a little notification.

@amoun Fixed in commit https://github.com/b2evolution/b2evolution/commit/0d33694b81f9868b7d5fe30356de18a4f60a22ee, thank you for the error searching!

@yurabakhtin

Thanks again, you seem pretty busy :)