It seem's, i have the problem on 2 Notebooks with Update from 15.10 => 16.04:
1st HP Elitebook with xubuntu, 2nd Dell Latitude with Ubuntu.
Maybe other logs are useful? F.e. my apt-term.log from the Dell-Nb.: /var/log/dist-upgrade/apt-term.log. See attachm.
It seem's, i have the problem on 2 Notebooks with Update from 15.10 => 16.04: dist-upgrade/ apt-term. log. See attachm.
1st HP Elitebook with xubuntu, 2nd Dell Latitude with Ubuntu.
Maybe other logs are useful? F.e. my apt-term.log from the Dell-Nb.: /var/log/