Install update errors, Install update, update - Chrome NO_PUBKEY

[stevef]

This indicates that a software signing key for chrome may be missing from your system. This is stopping your update/upgrade from working.

To help diagnose the problem, please can you open a terminal - by pressing Ctrl Alt and T together.
In the terminal window type or paste in this command followed by Enter.

Code:

ls -la /etc/apt/trusted.gpg.d/

This will show what keys you have installed in that directory.

Copy the output and paste it back here.