uploading

When i upload like a 600 mb file, when it gets completed, it will just hang as if it is still uploading but nothing happens and after awhile i get "Error: Internal Server Error" and though it seems to have still uploaded it, but takes so long in hanging at the end.

I have by Sync to my Reote server always Warning. Warnung: Only variables should be passed by reference in ..../dbtech/vboptimise_pro/includes/cdn/remote_server/cdn.php (Zeile 89) Uploading: clientscript/vbulletin_css/style00035r/friends.css... Warnung: Only variables should be passed by...