我读到，可以通过禁用或删除一些 Unity 作用域来加快仪表板中的应用程序搜索速度。我愚蠢地通过运行以下命令删除了所有作用域
sudo apt-get remove unity-scope*
我发现这导致删除了很多看似重要的软件包（例如nautilus）。它确实加快了搜索速度，但重启后，我的桌面就坏了。
我可以看到桌面，但没有菜单栏或启动器。我试过了sudo apt-get install ubuntu-desktop，但出现了以下错误：
The following packages have unmet dependencies:
ubuntu-desktop : Depends: checkbox-gui but it is not going to be installed
Recommends: unity-webapps-common but it is not going to be installed
Recommends: xul-ext-unity but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
我也尝试过sudo aptitude install ubuntu-desktop，但是出现了类似的错误：
The following NEW packages will be installed:
checkbox-gui checkbox-ng{a} checkbox-ng-service{a} libhud2{a} liboxideqt-qmlplugin{ab} liboxideqtcore0{a} libqt5feedback5{a} libqt5multimedia5{ab}
libqt5organizer5{ab} libqt5qml-graphicaleffects{a} libqt5svg5{a} libqt5webkit5-qmlwebkitplugin{a} libthumbnailer0{a} libunity-action-qt1{a} libunity-webapps0{a}
oxideqt-codecs{a} plainbox-provider-checkbox{a} plainbox-provider-resource-generic{a} plainbox-secure-policy{a} python3-checkbox-ng{a}
python3-checkbox-support{a} python3-plainbox{a} python3-pyparsing{a} python3-requests{a} python3-urllib3{a} qtdeclarative5-accounts-plugin{a}
qtdeclarative5-dialogs-plugin{a} qtdeclarative5-qtfeedback-plugin{a} qtdeclarative5-ubuntu-ui-extras-browser-plugin{a}
qtdeclarative5-ubuntu-ui-extras-browser-plugin-assets{a} qtdeclarative5-ubuntu-ui-toolkit-plugin{ab} qtdeclarative5-unity-action-plugin{a} ubuntu-desktop
ubuntu-ui-toolkit-theme{a} unity-webapps-common unity-webapps-qml{a} unity-webapps-service{a} webapp-container{ab} webbrowser-app{ab} xul-ext-unity
xul-ext-websites-integration{a}
0 packages upgraded, 41 newly installed, 0 to remove and 0 not upgraded.
Need to get 22,3 MB/25,2 MB of archives. After unpacking 99,9 MB will be used.
The following packages have unmet dependencies:
webapp-container : Depends: qtdeclarative-abi-5-2-1 which is a virtual package.
libqt5organizer5 : Depends: qtbase-abi-5-2-1 which is a virtual package.
webbrowser-app : Depends: qtdeclarative-abi-5-2-1 which is a virtual package.
libpython3.4-minimal : Breaks: python3-urllib3 (< 1.7.1-1ubuntu4) but 1.7.1-1build1 is to be installed.
libqt5multimedia5 : Depends: qtbase-abi-5-2-1 which is a virtual package.
qtdeclarative5-ubuntu-ui-toolkit-plugin : Depends: qtbase-abi-5-2-1 which is a virtual package.
Depends: qtdeclarative-abi-5-2-1 which is a virtual package.
liboxideqt-qmlplugin : Depends: qtdeclarative-abi-5-2-1 which is a virtual package.
The following actions will resolve these dependencies:
Keep the following packages at their current version:
1) checkbox-gui [Not Installed]
2) checkbox-ng [Not Installed]
3) checkbox-ng-service [Not Installed]
4) liboxideqt-qmlplugin [Not Installed]
5) libqt5feedback5 [Not Installed]
6) libqt5multimedia5 [Not Installed]
7) libqt5organizer5 [Not Installed]
8) libunity-webapps0 [Not Installed]
9) python3-checkbox-ng [Not Installed]
10) python3-requests [Not Installed]
11) python3-urllib3 [Not Installed]
12) qtdeclarative5-qtfeedback-plugin [Not Installed]
13) qtdeclarative5-ubuntu-ui-extras-browser-plugin [Not Installed]
14) qtdeclarative5-ubuntu-ui-toolkit-plugin [Not Installed]
15) ubuntu-desktop [Not Installed]
16) unity-webapps-common [Not Installed]
17) unity-webapps-qml [Not Installed]
18) unity-webapps-service [Not Installed]
19) webapp-container [Not Installed]
20) webbrowser-app [Not Installed]
21) xul-ext-unity [Not Installed]
22) xul-ext-websites-integration [Not Installed]
Accept this solution? [Y/n/q/?]
选择“y”会导致
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.
我已重置我的/etc/apt/sources.list：
deb http://us.archive.ubuntu.com/ubuntu/ trusty main universe
我已经跑过apt-get update好apt-get upgrade几次了。
我怎样才能解决这个问题？
编辑：
以下是 的输出apt-cache policy libpython3.4-minimal python3-urllib3 libqt5multimedia5：
libpython3.4-minimal:
Installed: 3.4.3-1ubuntu1~14.04.3
Candidate: 3.4.3-1ubuntu1~14.04.3
Version table:
*** 3.4.3-1ubuntu1~14.04.3 0
100 /var/lib/dpkg/status
3.4.0-2ubuntu1 0
500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages
python3-urllib3:
Installed: (none)
Candidate: 1.7.1-1build1
Version table:
1.7.1-1build1 0
500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages
libqt5multimedia5:
Installed: (none)
Candidate: 5.2.1-0ubuntu5
Version table:
5.2.1-0ubuntu5 0
500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages
100 /var/lib/dpkg/status
答案1
请尝试：
sudo dpkg -a --configure
sudo apt-get install unity