Thread:Project:Support desk/URLs are rewritten, but not redirecting/reply

You have $wgArticlePath set incorrectly somehow. MediaWiki thinks it is set to $wgArticlePath = "/w/index.php/$1";. Double check you don't have conflicting settings in LocalSettings.php or something like that. Try moving the $wgArticlePath = "/wiki/$1"; to the very end of the file.

You can check what mediawiki thinks the setting is by looking at: http://ilaisu.org/w/api.php?action=query&meta=siteinfo&siprop=general&format=txtfm