In Lubuntu 12.04 beta (final release in a few days).

I do not remember doing something outrageous to my PCManFM but now it has has a lot of problems:

• "extract here" menu action wouldn't work (this problem never disappears)

• the program shuts without obvious reason making the desktop empty (the program can be started in run (alt-f2) but this does not alway restore the desktop)

• would not start sometimes from its /usr/share/applications.desktop file (or the "Aplication Launch Bar") although it starts in run (alt-f2)

(the last problem is temporarily solved if the program is closed in task manager and than restarted with alt-f2)

I have reinstalled it to no avail.

Any ideas?