Problem solved(?) Many thanks! It seems that putting the correct permissions and usergroup on that one file fixed things all by itself. I was astonished when I got my usual graphics screen this morning, even before I tried apt-get update.
For the future, I will only become super-user if it seems necessary. I hope this avoids the /root congestion that seems to have been the start of this adventure. -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/20150219064951.20010...@debian.hsd1.il.comcast.net