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

No idea.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: redis-server (not installed)
ProcVersionSignature: Ubuntu 4.4.0-119.143-generic 4.4.114
Uname: Linux 4.4.0-119-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
Date: Fri Apr 6 20:19:02 2018
ErrorMessage: subprocess installed post-removal script returned error exit status 1
InstallationDate: Installed on 2017-08-22 (227 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.4
 apt 1.2.26
SourcePackage: redis
Title: package redis-server (not installed) failed to install/upgrade: subprocess installed post-removal script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)