How I solved my installation issue. When I ran deb package from command line sudo dpkg -i ~/Downloads/unity-editor-5.1.0f3+2015082501_amd64.deb This errors were found Selecting previously unselected package unity-editor. (Reading database ... 207627 files and directories currently installed.) Preparing to unpack unity-editor-5.1.0f3+2015082501_amd64.deb ... Unpacking unity-editor (5.1.0f3) ... dpkg: dependency problems prevent configuration of unity-editor: unity-editor depends on lib32gcc1 (>= 1:4.1.1); however: Package lib32gcc1 is not installed. unity-editor depends on lib32stdc++6 (>= 4.6); however: Package lib32stdc++6 is not installed. unity-editor depends on libc6-i386 (>= 2.15); however: Package libc6-i386 is not installed. dpkg: error processing package unity-editor (--install): dependency problems - leaving unconfigured Processing triggers for gnome-menus (3.10.1-0ubuntu2) ... Processing triggers for desktop-file-utils (0.22-1ubuntu1) ... Processing triggers for bamfdaemon (0.5.1+14.04.20140409-0ubuntu1+elementary2~ubuntu14.04.1) ... Rebuilding /usr/share/applications/bamf-2.index... Processing triggers for mime-support (3.54ubuntu1.1) ... Processing triggers for hicolor-icon-theme (0.13-1) ... Errors were encountered while processing: unity-editor The tried to met missing packages sudo apt-get install lib32gcc1 lib32stdc++6 libc6-i386 But... Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies. libc6-i386 : Depends: libc6 (= 2.19-0ubuntu6.9) but 2.19-0ubuntu6.7 is to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution). Finally ran sudo apt-get -f install sudo dpkg -i unity-editor-5.1.0f3+2015082501_amd64.deb And got Unity Editor installed. Great!