You seem to have some desktop packages installed but no desktop meta package. Please install one, probably xubuntu-desktop, and try the upgrade again.
2016-01-03 19:39:43,066 DEBUG need_server_mode(): can not find a desktop meta package or key deps, running in server mode ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1530703 Title: cant update To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1530703/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs