package initscripts 2.88dsf-59.2ubuntu2.1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[Cyprien]

every time I reboot my machine or try to install new packages

ProblemType: Package
DistroRelease: Ubuntu 15.10
Package: initscripts 2.88dsf-59.2ubuntu2.1
ProcVersionSignature: Ubuntu 4.2.0-25.30-generic 4.2.6
Uname: Linux 4.2.0-25-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
Date: Sun Jan 31 14:45:43 2016
DuplicateSignature: package:initscripts:2.88dsf-59.2ubuntu2.1:subprocess installed post-installation script returned error exit status 1
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2015-10-04 (119 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
RelatedPackageVersions:
 dpkg 1.18.2ubuntu5.1
 apt 1.0.10.2ubuntu1
SourcePackage: sysvinit
Title: package initscripts 2.88dsf-59.2ubuntu2.1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to wily on 2015-11-02 (91 days ago)

[Steve Langasek (vorlon)]

The error in your log is:

Setting up initscripts (2.88dsf-59.2ubuntu2.1) ...
insserv: warning: script 'K25vpnagentd_init' missing LSB tags and overrides
insserv: warning: script 'vpnagentd_init' missing LSB tags and overrides

This shows that you have a non-LSB init script on your system, not of Ubuntu origin, which prevents the upgrade from migrating you to dependency-based boot.

To get past this error, you should do one of:
 - contact the third-party provider of this init script to request an LSB-compatible upgrade
 - fix the script yourself
 - 'sudo rm /etc/rc?.d/*vpnagentd_init /etc/init.d/vpnagentd_init' to remove the offending script from your system.

[Launchpad Janitor (janitor)]

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