I have installed kubuntu-desktop on top of ubuntu 14.04 unity, then I purged kubuntu-desktop. Then i run command:
sudo apt-get remove libkde3support4 k3b-data ntrack-module-libnl-0 libkrosscore4 libgpgme++2 libqapt2 oxygen-icon-theme libktexteditor4 libtaskmanager4abi5 kdenetwork-filesharing libkblog4 libchm1 plasma-widgets-addons libkimap4 plasma-netbook libkdeui5 libkdeclarative5 ttf-oxygen-font-family gtk3-engines-oxygen user-manager gpgsm libakonadi-kcal4 kdepim-kresources libruby1.9.1 plymouth-theme-kubuntu-logo libqt4-sql-mysql libmailtransport4 kde-telepathy-filetransfer-handler kde-zeroconf libkpimtextedit4 konsole liblastfm1 libqjson0 libtag-extras1 libkdecorations4abi1 libkdcraw23 libkpeople3 kdepimlibs-kio-plugins libqrencode3 libkparts4 libakonadiprotocolinternals1 libbalooxapian4 akonadi-server nepomuk-core-data libqca2 kubuntu-notification-helper kdemultimedia-kio-plugins libntrack0 kde-runtime-data cdparanoia libplasma-geolocation-interface4 quassel-data libkemoticons4 libmessagecomposer4 libweather-ion6 cdrdao libnepomukquery4a bluedevil libakonadi-notes4 libkmediaplayer4 libksieveui4 muon-discover libmicroblog4 libnetworkmanagerqt1 libqt4-qt3support libkcddb4 amarok-utils libmailcommon4 libktpcommoninternalsprivate7 libprocessui4a katepart libmusicbrainz5-0 libkwineffects1abi4 libreoffice-base libkdepim4 kaddressbook soprano-daemon libmessageviewer4 libkwinglesutils1 libsoprano4 libqapt2-runtime vcdimager libcln6 libvirtodbc0 libbaloopim4 okular libqca2-plugin-ossl libkonq5abi1 ubuntu-release-upgrader-qt python3-pyqt4 libkephal4abi1 libksba8 kdesudo libqoauth1 gnupg-agent libxerces-c3.1 kde-telepathy-data kdelibs5-plugins kcalc libqmobipocket1 systemsettings libkolabxml1 libsyndication4 libkjsapi4 libplasmagenericshell4 libksane0 libkprintutils4 knotes libkactivities6 libincidenceeditorsng4 lightdm-kde-greeter libreoffice-sdbc-firebird libiso9660-8 kubuntu-docs amarok gwenview libkcalcore4 virtuoso-opensource-6.1-common libkmbox4 virtuoso-opensource-6.1-bin libakonadi-contact4 libakonadi-socialutils4 plasma-widget-kimpanel kde-touchpad python3-dbus.mainloop.qt libqtscript4-gui python3-pykde4 plasma-widget-menubar libxcb-record0 libkcompactdisc4 kde-config-telepathy-accounts libkabc4 libkunitconversion4 okular-extra-backends plymouth-theme-kubuntu-text libcryptsetup4 ktorrent-data libknewstuff3-4 kde-workspace-kgreet-plugins kde-config-tablet gstreamer0.10-qapt akregator libxcb-xtest0 libnepomukutils4 odbcinst1debian2 kate libkmanagesieve4 libprocesscore4abi1 libqtscript4-network libksane-data ibus-qt4 ttf-dejavu-core libyaml-0-2 libkxmlrpcclient4 plasma-nm libpam-ck-connector libqgpgme1 print-manager libksignalplotter4 libkipi-data klipper libakonadi-kmime4 gtk2-engines-oxygen kde-telepathy-text-ui libkhtml5 libkcal4 libkmime4 ksysguardd kontact libmailimporter4 libakonadi-calendar4 libprison0 libsendlater4 libntrack-qt4-1 libsignon-qt1 libkldap4 libkfile4 kubuntu-settings-desktop libpoppler-qt4-4 kamera libbaloofiles4 libtelepathy-qt4-2 libnoteshared4 libakonadi-kde4 libreoffice-kde icoutils libgrantlee-gui0 socat libkdepimdbusinterfaces4 audiocd-kio libmodemmanagerqt1 liboath0 libmessagecore4 libqtglib-2.0-0 kde-baseapps-bin kubuntu-driver-manager libattica0.4 libmygpo-qt1 libkdesu5 libknewstuff2-4 dragonplayer libdlrestrictions1 libgps20 kde-telepathy-send-file libstreams0 libkidletime4 libkateinterfaces4 libknotifyconfig4 qapt-deb-installer libtemplateparser4 about-distro dolphin kinfocenter libplasmaclock4abi4 amarok-common kaccessible libqtscript4-uitools libxcb-composite0 libkcalutils4 libreoffice-java-common usb-creator-kde libkdecore5 kdelibs-bin plasma-desktop skanlite kmag kdegraphics-strigi-analyzer nepomuk-core-runtime plasma-scriptengine-javascript libperl4-corelibs-perl qapt-batch kde-wallpapers-default libloudmouth1-0 libqaccessibilityclient0 libktnef4 libflac++6 libnepomuk4 libkleo4 odbcinst pam-kwallet libstreamanalyzer0 libkdcraw-data docbook-xsl libkntlm4 libopenconnect2 software-properties-kde ktorrent krdc kmousetool kde-workspace-data libqtscript4-core partitionmanager cryptsetup libvcdinfo0 libboost-thread1.54.0 libkfbapi1 libxcb-damage0 ruby1.9.1 libkcmutils4 libkpimidentities4 libreoffice-style-oxygen k3b libkworkspace4abi2 colord-kde libkfilemetadata4 kde-style-oxygen libdebconf-kde0 libktorrent-l10n libpolkit-qt-1-1 libkolab0 libepub0 libkdgantt2-0 kubuntu-settings-netbook libqtscript4-xml kubuntu-web-shortcuts libtelepathy-logger-qt4-1 libkactivities-models1 libkpimutils4 freespacenotifier pinentry-qt4 kde-config-gtk-style libkgapi2-2 baloo libkubuntu0 python3-sip kmix libkio5 libxml2-utils ksnapshot libktorrent5 libakonadi-kabc4 libpimcommon4 kde-config-whoopsie libkpgp4 khelpcenter4 oxygen-cursor-theme shared-desktop-ontologies libkexiv2-data libplasma3 muon-updater kde-config-pimactivity kde-telepathy libaccounts-qt1 kdepasswd libqtscript4-sql libkexiv2-11 libkontactinterface4 libmessagelist4 kde-telepathy-integration-module kdepim-runtime libkscreen1 && sudo apt-get install ubuntu-desktop
as described in http://askubuntu.com/questions/451620/how-to-completely-remove-kubuntu-desktop-from-ubuntu/488284#488284
Output said, that it removes cryptsetup and I will not be able to mount encrypted devices. I run:
sudo apt-get install cryptsetup hashalot initramfs-tools
Now, when unity starts it throws crpyptsetup crash window.
ProblemType: Package
DistroRelease: Ubuntu 14.04
Package: cryptsetup 2:1.6.1-1ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-59.66~14.04.1-generic 3.19.8-ckt19
Uname: Linux 3.19.0-59-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
Date: Wed Jun 8 13:53:03 2016
DuplicateSignature: package:cryptsetup:2:1.6.1-1ubuntu1:subprocess installed pre-removal script returned error exit status 1
ErrorMessage: subprocess installed pre-removal script returned error exit status 1
InstallationDate: Installed on 2016-01-19 (140 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
RelatedPackageVersions:
dpkg 1.17.5ubuntu5.6
apt 1.0.1ubuntu2.14
SourcePackage: cryptsetup
Title: package cryptsetup 2:1.6.1-1ubuntu1 failed to install/upgrade: subprocess installed pre-removal script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)
crypttab: sda5_crypt UUID=55808ea8-65c2-4ec4-9408-8298e15692eb none luks,discard
Status changed to 'Confirmed' because the bug affects multiple users.