Hi, I'm quite confuse about this error. If you go in this link: http://dcs.di.unipmn.it/wiki/index.php/Param-sim#BoT_Size you can see the error:* "Failed to parse (PNG conversion failed; * *check for correct installation of latex, dvips, gs, and convert): z*" What is surprise me most is that, if I change it to <math>Median</math> at it was before, I do not get any error. Do you have any idea about this? Today, I have just restarted apache since I have changenged the "max upload file size" and I have added "pdf" as one of the possible file extensions. Thanks, Massimo