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

[Christian Dysthe]

I installed and purged this package but it still gives me this error message now and then. I tried to reinstall inn but now I get this error:

Job for inn.service failed. See "systemctl status inn.service" and "journalctl -xe" for details.
invoke-rc.d: initscript inn, action "start" failed.
dpkg: error processing package inn (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 inn

ProblemType: Package
DistroRelease: Ubuntu 15.04
Package: inn (not installed)
ProcVersionSignature: Ubuntu 3.19.0-15.15-generic 3.19.3
Uname: Linux 3.19.0-15-generic x86_64
ApportVersion: 2.17.2-0ubuntu1
AptOrdering:
 postfix: Install
 inn: Install
 postfix: Configure
 inn: Configure
 NULL: ConfigurePending
Architecture: amd64
Date: Sat Apr 25 23:49:56 2015
DuplicateSignature: package:inn:(not installed):subprocess installed post-installation script returned error exit status 1
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2015-04-24 (2 days ago)
InstallationMedia: It
RelatedPackageVersions:
 dpkg 1.17.25ubuntu1
 apt 1.0.9.7ubuntu4
SourcePackage: inn
Title: package inn (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.