I'm hoping a user who has successfully installed the GraphViz extension can help me troubleshoot this. You can reply directly to me at < mpd2002(a)columbia.edu&gt; if you prefer. I've followed the install instructions<http://www.mediawiki.org/wiki/Extension:GraphViz>for the GraphViz extension and so far everything seems OK - GraphViz dot commands work, permissions look fine - but although the page is parsing the graphviz content, my wiki page still fails to show any graphics: http://www.mathewdavies.com/wiki/index.php?title=Ideologi Usually there is an error that the map file is not found on line 420 of GraphViz.php (should be visible on the page linked above). When I look in the referenced image directory, there's nothing, so I'm guessing that for some reason the GraphViz extension is not sending output to the GraphViz image directory, although I don't see anything in the configuration that would cause problems. (I don't think write access is a problem since I've granted access to the image directory). Any idea what's happening? I've looked all over the web and haven't found anything that helps me troubleshoot. Unfortunately I'm not good enough with PHP to trace what the extension is actually doing. Would be grateful for any suggestions. Sincerely, - Mathew (mpd2002(a)columbia.edu)