I have received exactly the same error message, same Bug #1513260, when I tried to update Lubuntu 14.4.
A few weeks before I had edited the file /etc/environment and added another line. Now I undid this change, so that only one line with the path remained in the file /etc/environment. After this change I could update Lubuntu whithout problem.
Maybe this can help you.
I have received exactly the same error message, same Bug #1513260, when I tried to update Lubuntu 14.4.
A few weeks before I had edited the file /etc/environment and added another line. Now I undid this change, so that only one line with the path remained in the file /etc/environment. After this change I could update Lubuntu whithout problem.
Maybe this can help you.