Невозможно открыть софт-центр в Ubuntu 13.04

Когда я нажимаю на Ubuntu Software Center, он ничего не делает. Не могли бы вы помочь заставить его работать?

Также я попытался обновить & amp; обновить, но бесполезно. Я пробовал это через терминал, используя software-center, тогда он выдает эту ошибку.

abdul@abdul-Lenovo-G580:~/git/Flex-Voicemail/voicemail$ software-center
2013-07-10 08:44:15,044 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None'
2013-07-10 08:44:15,088 - softwarecenter.fixme - WARNING - logs to the root logger:         '('/usr/lib/python2.7/dist-packages/dbus/proxies.py', 410, '_introspect_error_handler')'
2013-07-10 08:44:15,088 - dbus.proxies - ERROR - Introspect error on  com.ubuntu.sso:/com/ubuntu/sso/credentials: dbus.exceptions.DBusException:  org.freedesktop.DBus.Error.Spawn.ChildExited: Process /usr/lib/ubuntu-sso-client/ubuntu- sso-login exited with status 1
Traceback (most recent call last):
File "/usr/bin/software-center", line 130, in <module>
app = SoftwareCenterAppGtk3(options, args)
File "/usr/share/software-center/softwarecenter/ui/gtk3/app.py", line 338, in  __init__
self.icons)
File "/usr/share/software-center/softwarecenter/ui/gtk3/session/appmanager.py", line 66, in __init__
self.oauth_token = helper.find_oauth_token_sync()
File "/usr/share/software-center/softwarecenter/backend/ubuntusso.py", line 141, in find_oauth_token_sync
sso.find_credentials()
File "/usr/share/software-center/softwarecenter/backend/login_impl/login_sso.py", line 75, in find_credentials
self.proxy.find_credentials(self.appname, self._get_params())
File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 70, in __call__
return self._proxy_method(*args, **keywords)
File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 145, in __call__
**keywords)
File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 651, in call_blocking
message, timeout)
dbus.exceptions.DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Process   /usr/lib/ubuntu-sso-client/ubuntu-sso-login exited with status 1