packages cannot be authenticated

I started using a new image:

root@beaglebone:~# cat /etc/dogtag Debian Image 2015-11-21

I am getting a complaint about "packages cannot be authenticated!". I
wonder why. Should the Debian keys not be part of the image? I did not
have this problem with older BB images.

sync your clock and refresh the apt cache..

sudo apt-get update


Thanks. That fixed it.
I had done "apt-get update" several times, but then I rebooted the BBB
without doing it again after the last boot.

Humm, that shouldn't have mattered, wonder if your clock didn't get
resynced.. (wheezy: ntpdate (only at bootup), jessie: systemd


I have the ntp package installed, just like with my previous BBB image
of September. It seems to work because if I power it off and on my
time is still correct. So not sure what is going on.