正如你所看到的，我是一个 Linux 菜鸟。我还没有升级我的 ubuntu 17.04，这让我很头疼。我根本不能使用 apt-get。我想这背后的原因是我的版本缺乏支持。我尝试遵循一些教程，包括这个：https://help.ubuntu.com/community/EOLUpgrades 无论我做什么或是否更新 sources.list，apt-get 似乎仍然不受支持。
例如，如果我运行 apt-get update，我会得到以下响应：
Reading package lists... Done
W: The repository 'http://ppa.launchpad.net/ehbello/fritzing/ubuntu zesty Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: The repository 'http://ppa.launchpad.net/js-reynaud/kicad-5/ubuntu zesty Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://ppa.launchpad.net/ehbello/fritzing/ubuntu/dists/zesty/main/binary-i386/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/js-reynaud/kicad-5/ubuntu/dists/zesty/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
否则，运行 apt-get upgrade 会给我：
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies: mono-devel : Depends: mono-roslyn (= 5.10.1.20-0xamarin1+debian7b1) but it is not installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).
apt --fix-broken install 的结果是：
enter code here
After this operation, 13,6 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
dpkg: warning: files list file for package 'mono-devel' missing; assuming package has no files currently installed
dpkg: warning: files list file for package 'monodoc-base' missing; assuming package has no files currently installed
dpkg: warning: files list file for package 'monodoc-manual' missing; assuming package has no files currently installed
(Reading database ... 266394 files and directories currently installed.)
Preparing to unpack .../mono-roslyn_5.10.1.20-0xamarin1+debian7b1_all.deb ...
Unpacking mono-roslyn (5.10.1.20-0xamarin1+debian7b1) ...
dpkg: error processing archive /var/cache/apt/archives/mono-roslyn_5.10.1.20-0xamarin1+debian7b1_all.deb (--unpack):
trying to overwrite '/usr/bin/csc', which is also in package chicken-bin 4.11.0-1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Errors were encountered while processing:
/var/cache/apt/archives/mono-roslyn_5.10.1.20-0xamarin1+debian7b1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
上面的链接使用 aptitude 来安装所需的软件包，但是我找不到不使用 apt-get 来安装它的方法。
提前致谢。
更新 这就是我的 sources.list 文件的样子：
deb http://old-releases.ubuntu.com/ubuntu/ zesty main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ zesty-updates main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ zesty-security main restricted universe multiverse