"IndexError: could not find tree path" when opening preferences

[Geoffroy Ménard]

Just updated to 0.56 version using the unofficial PPA. When I try to open the preferences, I get the following error dialog

IndexError: could not find tree path

This is zim 0.54
Python version is sys.version_info(major=2, minor=7, micro=3, releaselevel='final', serial=0)
Gtk version is (2, 24, 10)
Pygtk version is (2, 24, 0)
Platform is posix
No bzr version-info found

======= Traceback =======
  File "/usr/lib/python2.7/dist-packages/zim/gui/__init__.py", line 820, in _action_handler
  File "/usr/lib/python2.7/dist-packages/zim/gui/__init__.py", line 1676, in show_preferences
  File "/usr/lib/python2.7/dist-packages/zim/gui/preferencesdialog.py", line 96, in __init__
  File "/usr/lib/python2.7/dist-packages/zim/gui/preferencesdialog.py", line 256, in __init__
  File "/usr/lib/python2.7/dist-packages/zim/gui/preferencesdialog.py", line 259, in do_row_activated
IndexError: could not find tree path

I don't know why zim identifies itself as 0.54, because Aptitude identified the package I upgraded to as 0.56

[Jaap Karssenberg (jaap.karssenberg)]

Please close all instances of zim first (including tray icon), maybe
there was still a process running as 0.54.

Regards,

Jaap

[Geoffroy Ménard (d-geoffm)]

You're right, that was the problem, because of the confusion induced when we expect to close a program and instead of closing it minimizes to the tray...