After upgrading to ubuntu 13.04, i have the same problem here. I have no zope package in my python dist packages.
~$ software-center 2013-04-27 05:56:26,937 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None' 2013-04-27 05:56:27,229 - softwarecenter.fixme - WARNING - logs to the root logger: '('/usr/lib/python2.7/dist-packages/dbus/proxies.py', 410, '_introspect_error_handler')' 2013-04-27 05:56:27,229 - 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 ~$ /usr/lib/ubuntu-sso-client/ubuntu-sso-login Traceback (most recent call last): File "/usr/lib/ubuntu-sso-client/ubuntu-sso-login", line 67, in <module> from ubuntu_sso.main import main File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/main/__init__.py", line 42, in <module> from ubuntu_sso.account import Account File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/account.py", line 48, in <module> from ubuntu_sso.utils.webclient.common import WebClientError File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/utils/webclient/common.py", line 34, in <module> from oauthlib.oauth1 import ( ImportError: cannot import name SIGNATURE_HMAC -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1085425 Title: Crash in software-center when starting service com.ubuntu.sso To manage notifications about this bug go to: https://bugs.launchpad.net/software-center/+bug/1085425/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs