Traceback (most recent call last):
  File "/usr/bin/software-center", line 107, in <module>
    from softwarecenter.app import SoftwareCenterApp
  File "/usr/share/software-center/softwarecenter/app.py", line 43, in <module>
    from softwarecenter.view.softwarepane import wait_for_apt_cache_ready
  File "/usr/share/software-center/softwarecenter/view/softwarepane.py", line 50, in <module>
    from  appdetailsview_gtk import AppDetailsViewGtk as AppDetailsView
  File "/usr/share/software-center/softwarecenter/view/appdetailsview_gtk.py", line 37, in <module>
    from softwarecenter.backend.zeitgeist_simple import zeitgeist_singleton
  File "/usr/share/software-center/softwarecenter/backend/zeitgeist_simple.py", line 101, in <module>
    zeitgeist_singleton = SoftwareCenterZeitgeist()
  File "/usr/share/software-center/softwarecenter/backend/zeitgeist_simple.py", line 37, in __init__
    self.zg_client = ZeitgeistClient()
  File "/usr/lib/pymodules/python2.7/zeitgeist/client.py", line 311, in __init__
    self._iface = ZeitgeistDBusInterface()
  File "/usr/lib/pymodules/python2.7/zeitgeist/client.py", line 187, in __init__
    self.INTERFACE_NAME, self.OBJECT_PATH)
  File "/usr/lib/pymodules/python2.7/zeitgeist/client.py", line 124, in __init__
    self.__methods, self.__signals = self.get_members(proxy.Introspect())
  File "/usr/lib/pymodules/python2.7/dbus/proxies.py", line 68, in __call__
    return self._proxy_method(*args, **keywords)
  File "/usr/lib/pymodules/python2.7/dbus/proxies.py", line 140, in __call__
    **keywords)
  File "/usr/lib/pymodules/python2.7/dbus/connection.py", line 630, in call_blocking
    message, timeout)
DBusException: org.freedesktop.DBus.Error.ServiceUnknown: The name :1.263 was not provided by any .service files