package squid (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[Andi Chandler]

.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: squid (not installed)
ProcVersionSignature: Ubuntu 4.2.0-34.39-generic 4.2.8-ckt4
Uname: Linux 4.2.0-34-generic x86_64
ApportVersion: 2.20.1-0ubuntu1
Architecture: amd64
Date: Mon Apr 11 13:15:16 2016
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2014-08-26 (593 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Alpha amd64 (20140826)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1
 apt 1.2.10
SourcePackage: squid3
Title: package squid (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Robie Basak (racb)]

From log:

Setting up squid (3.5.12-1ubuntu6) ...
Removing obsolete conffile /etc/squid3/msntauth.conf ...
Preserving user changes to /etc/squid/squid.conf (renamed from /etc/squid3/squid.conf)...
stat: cannot stat '/var/spool/squid3': No such file or directory
chown: cannot access '/var/spool/squid3': No such file or directory
dpkg: error processing package squid (--configure):
 subprocess installed post-installation script returned error exit status 1

[Robie Basak (racb)]

This may be a duplicate of bug 1613914.

[Christian Ehrhardt  (paelzer)]

There was no further feedback considering this a dup or not.
For now I'll mark it as such so that the reporter here gets notified once the other gets solved.
If this does not address the issues here we can still un-dup it.
But for now this is better than just marking this bug over here incomplete.