apt-key fails silently

[Owen]

The apt-key command just returns to the command prompt with no output. I am sure it's failing or crashing silently. The scenario is that I am getting the pgdg-keyring /usr/bin/dpkg returned an error code (1) issue. Following the instructions in a forum posting I moved all the files from /etc/apt/trusted.gpg.d and re-ran apt-get update. This reported several unverified keys. I then started adding the keys by running apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys foo and noticed there was no output and it returned to the command prompt too quickly. Also no keys were added. Unfortunately moving all the .gpg files back into /etc/apt/trusted.gpg.d has left me with three unverified keys; http://apt.postgresql.org and two for http://ppa.launchpad.net. apt.postgresql seemed to be the key that was causing the original pgdg-keyring, but this could also be because it was the first in the list and all the others would also fail.

Description: Ubuntu 14.04.1 LTS
Release: 14.04

  Installed: 1.0.1ubuntu2.4.1
  Candidate: 1.0.1ubuntu2.4.1
  Version table:
 *** 1.0.1ubuntu2.4.1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
        100 /var/lib/dpkg/status
     1.0.1ubuntu2 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: apt 1.0.1ubuntu2.4.1
Uname: Linux 3.17.0-031700rc6-lowlatency x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.4
Architecture: amd64
CurrentDesktop: KDE
Date: Thu Sep 25 13:39:01 2014
SourcePackage: apt
UpgradeStatus: No upgrade log present (probably fresh install)