Dear All, I¹m having this error while trying to run the CalendarServer on Snow Leopard: Starting server... exec python /Users/gede/Documents/Projects/Twisted/bin/twistd caldav -f /Users/gede/Documents/Projects/CalendarServer/conf/caldavd-dev.plist -o ProcessType=Combined Traceback (most recent call last): File "/Users/gede/Documents/Projects/Twisted/bin/twistd", line 19, in <module> run() File "/Users/gede/Documents/Projects/Twisted/twisted/scripts/twistd.py", line 27, in run app.run(runApp, ServerOptions) File "/Users/gede/Documents/Projects/Twisted/twisted/application/app.py", line 689, in run config.parseOptions() File "/Users/gede/Documents/Projects/Twisted/twisted/application/app.py", line 669, in parseOptions usage.Options.parseOptions(self, options) File "/Users/gede/Documents/Projects/Twisted/twisted/python/usage.py", line 226, in parseOptions for (cmd, short, parser, doc) in self.subCommands: File "/Users/gede/Documents/Projects/Twisted/twisted/application/app.py", line 680, in subCommands self.loadedPlugins[plug.tapname] = plug File "/Users/gede/Documents/Projects/CalendarServer/twisted/plugins/caldav.py", line 13, in getProperty return getattr(reflect.namedClass(self.serviceMakerClass), propname) File "/Users/gede/Documents/Projects/Twisted/twisted/python/reflect.py", line 349, in namedObject module = namedModule('.'.join(classSplit[:-1])) File "/Users/gede/Documents/Projects/Twisted/twisted/python/reflect.py", line 337, in namedModule topLevel = __import__(name) File "/Users/gede/Documents/Projects/CalendarServer/calendarserver/sidecar/task.p y", line 24, in <module> from calendarserver.provision.root import RootResource File "/Users/gede/Documents/Projects/CalendarServer/calendarserver/provision/root .py", line 31, in <module> from twistedcaldav.extensions import DAVFile, CachingPropertyStore File "/Users/gede/Documents/Projects/CalendarServer/twistedcaldav/extensions.py", line 65, in <module> from twistedcaldav.method.report import http_REPORT File "/Users/gede/Documents/Projects/CalendarServer/twistedcaldav/method/report.p y", line 31, in <module> from twext.web2.dav.davxml import ErrorResponse File "/Users/gede/Documents/Projects/CalendarServer/twext/web2/dav/__init__.py", line 28, in <module> twisted.web2.dav.davxml.registerElements(davxml) File "/Users/gede/Documents/Projects/Twisted/twisted/web2/dav/element/parser.py", line 65, in registerElements registerElement(element_class, element_names) File "/Users/gede/Documents/Projects/Twisted/twisted/web2/dav/element/parser.py", line 78, in registerElement % (qname, elements_by_tag_name[qname], element_class) AssertionError: Attempting to register qname ('DAV:', 'error') multiple times: (<class 'twisted.web2.dav.element.rfc3253.Error'>, <class 'twisted.web2.dav.element.rfc3253.Error'>) launchctl bsexec failed: No such file or directory I¹m sorry, I¹m a newbie. Is anyone having the same problem? Thank you in advance.