Wrong code.

Try this:

$icon = elgg_view_entity_icon($user, 'large', array('use_link' => false, 'use_hover' => false));

$url = elgg_view('output/url', array(
    'href' => $icon,
    'text' => $icon,
    'class' => 'elgg-lightbox',
));

echo $url;

@RvR I tried it, but it's not working. Now i can't click on the picture to open the lightbox.

Missing

$icon = elgg_view_entity_icon($user, 'large', array('use_link' => false, 'use_hover' => false));

$url = elgg_view('output/url', array(
    'href' => '#',
    'text' => $icon,
    'link_class' => 'elgg-lightbox',
));

echo $url;

Yes, i have my own plug-in and did everything right i think. Now i moved it to another plugin-in and it works, but only in firefox. in chrome it stills shows this white bar.

the url is testse.locoflirt.com

First, you seem to use some plugins (at least the bulk_image_upload plugin) that are not fully compatible with Elgg 1.8. While this might not be connected with the language file issue, this could also result in issues (not saying that there are issues is any case when using outdated plugins as some might fully work on Elgg 1.8 even if they were released for older Elgg versions originally but there could be errors).

For the language file issue it could be either a problem caused by the encoding you saved the language file in: http://docs.elgg.org/wiki/Development/Contributing/Languages.

Or it could be some invalid character used or there's a syntax error in the language file array (basically, it's a php array that you fill with the language strings).

If your language file is not too long, you could add it here or you could add it at pastebin for us to take a look at it.

I solved the problem. The coding was the problem.

I only had selected UTF-8, but in my editor i didn't had the option to deactivate BOM.

With notepad++ it's possible to select UTF-8 without BOM.

Thx for helping!

foreach($messages as $message){
$user = get_entity($message->fromId);
}

Use the 'metadata_case_sensitive' parameter: http://reference.elgg.org/engine_2lib_2metadata_8php.html#aec4b6f0b9565e3554acb9b39ef34a2ac