Are you using Extension Manager CS5 or CS5.5 on Mac 10.8? If yes, you have to install CS5.0.3 or CS5.5.3 update. We released these two updates one year ago. Please go to http://www.adobe.com/downloads/updates/ and search "Extension Manager 5.5.3 update" and "Extension Manager 5.0.3 update". If no, please provide more details.