我已经尝试查找所有可能的 Ubuntu 更新问题论坛，但是我似乎找不到任何可行的方法。我似乎无法弄清楚如何解决它一直说无法找到带有 Zesty 的包或文件的问题。下面我复制了我输入时得到的代码sudo apt-get update。
Ign:1 http://archive.ubuntu.com/ubuntu zesty InRelease
Hit:2 http://ppa.launchpad.net/fenics-packages/fenics/ubuntu zesty InRelease
Ign:3 http://archive.ubuntu.com/ubuntu zesty-updates InRelease
Ign:4 http://archive.ubuntu.com/ubuntu zesty-backports InRelease
Ign:5 http://ppa.launchpad.net/ubuntu-audio-dev/ppa/ubuntu zesty InRelease
Ign:6 http://archive.ubuntu.com/ubuntu zesty-security InRelease
Err:7 http://archive.ubuntu.com/ubuntu zesty Release
404 Not Found [IP: 91.189.88.152 80]
Ign:8 http://ppa.launchpad.net/ubuntu-audio-dev/ppa/ubuntu zesty Release
Err:9 http://archive.ubuntu.com/ubuntu zesty-updates Release
404 Not Found [IP: 91.189.88.152 80]
Err:10 http://archive.ubuntu.com/ubuntu zesty-backports Release
404 Not Found [IP: 91.189.88.152 80]
Err:11 http://archive.ubuntu.com/ubuntu zesty-security Release
404 Not Found [IP: 91.189.88.152 80]
Ign:12 http://ppa.launchpad.net/ubuntu-audio-dev/ppa/ubuntu zesty/main …