TL;DR The issue for me lied in /etc/bash.bashrc This line near the bottom: python /usr/lib/command-not-found -- $1
should be: /usr/lib/command-not-found -- $1 Long explanation follows: I had the same issue. For me issue occurred whenever I mistyped a command. /usr/lib/command-not-found is a python program. I found that if I ran it like: python3.3 /usr/lib/command-not-found bad-command it ran fine, but python /usr/lib/command-not-found bad-command Resulted in: Traceback (most recent call last): File "/usr/lib/python3.3/site.py", line 631, in <module> main() File "/usr/lib/python3.3/site.py", line 616, in main known_paths = addusersitepackages(known_paths) File "/usr/lib/python3.3/site.py", line 284, in addusersitepackages user_site = getusersitepackages() File "/usr/lib/python3.3/site.py", line 260, in getusersitepackages user_base = getuserbase() # this will also set USER_BASE File "/usr/lib/python3.3/site.py", line 250, in getuserbase USER_BASE = get_config_var('userbase') File "/usr/lib/python3.3/sysconfig.py", line 580, in get_config_var return get_config_vars().get(name) File "/usr/lib/python3.3/sysconfig.py", line 530, in get_config_vars _init_posix(_CONFIG_VARS) File "/usr/lib/python3.3/sysconfig.py", line 403, in _init_posix from _sysconfigdata import build_time_vars File "/usr/lib/python3.3/_sysconfigdata.py", line 6, in <module> from _sysconfigdata_m import * ImportError: No module named '_sysconfigdata_m' The issue lied in /etc/bash.bashrc This line near the bottom: python /usr/lib/command-not-found -- $1 was invoking python 2. Changing it to: python3.3 /usr/lib/command-not-found -- $1 or just plain: /usr/lib/command-not-found -- $1 fixed the problem for me :) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1192890 Title: update-manager fails to upgrade from quantal to raring No module named '_sysconfigdata_m' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python3.3/+bug/1192890/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs