I had the same problem. I don't know if this happenede because I upgraded to a dev version of ubuntu and if this problem would not occur for updates to the release version of feisty. Nevertheless, if the pickle-file is corrupt for whatever reason, it would be nice if gnome-app-install would recover from that error. The attached patch should do the job.
** Attachment added: "Patch that makes gnome-app-install NOT crash if pickle-file cannot be read" http://librarian.launchpad.net/5780844/gnome-app-install_pickle_crash.patch -- Add/Remove programs crashed on Feisty https://launchpad.net/bugs/79619 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
