Comment 2 for bug 1690667

The error in your log is:

Processing triggers for shim-signed (1.28+0.9+1474479173.6c180c6-1ubuntu1) ...
debconf: unable to initialize frontend: Passthrough
debconf: (Cannot connect to /tmp/aptdaemon-b22qmfzw/debconf.socket: Connection refused at (eval 17) line 3.)
debconf: falling back to frontend: Noninteractive
Running in non-interactive mode, doing nothing.
dpkg: error processing package shim-signed (--configure):

Looks like something went wrong with aptdaemon's connection to the frontend.

How did you select the nvidia drivers for installation?