Okay, a few weeks ago my wiki stopped loading. The version I've got installed there is ancient, but it was working fine until one day it wasn't.
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Parse error: syntax error, unexpected T_NAMESPACE, expecting T_STRING in /hermes/bosoraweb123/b65/ipw.joshua-w/public_html/wiki/includes/Namespace.php on line 46
Your PHP was upgraded, and the old MediaWiki software will not work with it. One of the reasons is that "namespace" is now a reserved word. The best and easiest solution is to upgrade your wiki, but there are others:
http://blog.endpoint.com/2015/11/broken-wikis-due-to-php-and-mediawiki.html