在ubuntu 14.04中缺少Canonical合作伙伴和独立存储库
当我发现Canonical合作伙伴和独立存储库从“软件和更新”的“其他软件”选项卡中丢失时，我今天遇到了一个奇怪的问题。 我还注意到“主要”，“宇宙”，“多元宇宙”和“受限制”都被禁用，以及“trusy-security”，“trusty-updates”，“trusy-proposed”和“trusty-backports”。
问题是：如何添加Canonical和独立存储库以便我可以重新启用它们？ 什么可能导致这个？
先感谢您。
打开终端（Ctrl + Alt + T）然后运行：
sudo gedit /etc/apt/sources.list 用以下内容替换所有文本：
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://archive.ubuntu.com/ubuntu/ trusty main restricted # deb-src http://archive.ubuntu.com/ubuntu/ trusty main restricted ## Major bug fix updates produced after the final release of the ## distribution. deb http://archive.ubuntu.com/ubuntu/ trusty-updates main restricted # deb-src http://archive.ubuntu.com/ubuntu/ trusty-updates main restricted ## NB software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://archive.ubuntu.com/ubuntu/ trusty universe # deb-src http://archive.ubuntu.com/ubuntu/ trusty universe deb http://archive.ubuntu.com/ubuntu/ trusty-updates universe # deb-src http://archive.ubuntu.com/ubuntu/ trusty-updates universe ## NB software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://archive.ubuntu.com/ubuntu/ trusty multiverse # deb-src http://archive.ubuntu.com/ubuntu/ trusty multiverse deb http://archive.ubuntu.com/ubuntu/ trusty-updates multiverse # deb-src http://archive.ubuntu.com/ubuntu/ trusty-updates multiverse ## NB software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse # deb-src http://archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse deb http://security.ubuntu.com/ubuntu trusty-security main restricted # deb-src http://security.ubuntu.com/ubuntu trusty-security main restricted deb http://security.ubuntu.com/ubuntu trusty-security universe # deb-src http://security.ubuntu.com/ubuntu trusty-security universe deb http://security.ubuntu.com/ubuntu trusty-security multiverse # deb-src http://security.ubuntu.com/ubuntu trusty-security multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu trusty partner # deb-src http://archive.canonical.com/ubuntu trusty partner ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software. deb http://extras.ubuntu.com/ubuntu trusty main # deb-src http://extras.ubuntu.com/ubuntu trusty main
保存，关闭gedit，然后运行：
sudo apt-get update