apt-get无法下载，一些网址Not Found 404
apt-get无法下载，网址报 Not Found 404，原因是apt软件下载源有问题。
1.将/etc/apt/source.list里的内容替换。
在其它可以下载apt的ubuntu机器中拷贝过来覆盖此文件，再执行apt-get update更新source list。
2.“软件更新管理”->"设置"->“ubuntu软件”->“下载自”中修改软件下载源。
转自： http://blog.csdn.net/cjsycyl/article/details/32702745
有时会遇到能 ping 通外网，但是无法更新软件的情况。
如： 正在读取软件包列表... 有错误！？？
解决方法如下：
sudo apt-get clean
cd /var/lib/apt
sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt-get clean
sudo apt-get update
5.2安装编译环境的软件可能会出现的问题
下列软件包有未满足的依赖关系： libasound2: 破坏: libasound2-plugins (< 1.0.24-0ubuntu3) 但是 1.0.22-0ubuntu6 正要被安装 libglib2.0-0: 破坏: gnome-control-center (< 1:3) 但是 1:2.30.0-0ubuntu4 正要被安装 ppp: 破坏: network-manager (<= 0.8.0.999-1) 但是 0.8-0ubuntu3 正要被安装E: 破损的软件包
某些源有问题,为高版本 ubuntu的源 ,删除即可,如安装高版本的git所用的源就是ubuntu 10.4之后的源，用在10.04上就可以会有问题，引起此提示。
在终端中执行：gedit /etc/apt/source.list
把文件的最后 deb http://ftp.de.debian.org/debian sid main 删除，并保存退出
回到终端中执行：sudo apt-get update
再次重新安装编译环境的软件
对于不同的版本使用的是不同的库，如下，根据不同版本，替换名称即可。
lucid（10.04）
Natty(11.04)
Oneiric(11.10)
Precise(12.04)
Quantal(12.10)
Utopic（14.10）
Vivid（15.04）
Wily(15.10)
Xenial（16.04）
ubuntu 10.04 更新源 sources.list（我用的是网易的源）
Ubuntu系统下更新 sources.list
在终端执行以下命令（第一条是备份现有服务器列表，第二条是使用Gedit编辑，您也可以使用自己喜爱的编辑器编辑。）
（如果你设置的是非中文环境，但需要系统提供中文支持，那么请按照以下情况执行命令：sudo apt-get install language-pack-zh，正常的升级方法是，选择“System”->“系统管理”->“Language Support”，系统会自动加载所需语言文件。）
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
sudo gedit /etc/apt/sources.list
从以下各服务器列表内容中选择一段替换文件中的所有内容（请根据自己网络环境设置更新服务器，以达到最快的速度。）
* Archive.ubuntu.com 更新服务器(欧洲)：
#
deb http://archive.ubuntu.com/ubuntu/ dapper main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-updates main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-backports main restricted universe multiverse
deb http://archive.ubuntu.org.cn/ubuntu-cn/ dapper main restricted universe multiverse
* Ubuntu.cn99.com 更新服务器(江苏省常州市电信，推荐电信用户使用。）：
deb http://ubuntu.cn99.com/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-security main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu-cn/ dapper main restricted universe multiverse
* Mirror.lupaworld.com 更新服务器(浙江省杭州市电信，亚洲地区官方更新服务器，推荐全国用户使用。）：
deb http://cn.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu/ubuntu-cn dapper main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
* 上海市 上海交通大学 更新服务器（教育网，推荐校园网和网通用户使用。）(目前已无法使用)：
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-backports main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-proposed main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-security main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-updates main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper main multiverse restricted universe
* 北京市清华大学 更新服务器（教育网，推荐校园网和网通用户使用。)：
deb http://mirror9.net9.org/ubuntu/ dapper main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ dapper-backports main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ dapper-proposed main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ dapper-security main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ dapper-updates main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu-cn/ dapper main multiverse restricted universe
* 中国 台湾省台湾大学 更新服务器（推荐网通用户使用，电信PING平均响应速度41MS。）(强烈推荐,此源比较完整,较少出现同步问题)
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-security main restricted universe multiverse
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper main multiverse restricted universe
* Mirror.vmmatrix.net 更新服务器（上海市电信，推荐电信网通用户使用。）(目前已无法使用):
deb http://mirror.vmmatrix.net/ubuntu/ dapper main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-updates main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-backports main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-security main restricted universe multiverse
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper main multiverse restricted universe
ubuntu.cnsite.org 更新服务器 (福建省福州市 电信):
deb http://ubuntu.cnsite.org/ubuntu/ dapper main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-security main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu-cn/ dapper main multiverse restricted universe
*
到以下网址可以自定义产生若干源：http://www.ubuntulinux.nl/source-o-matic 以下网址有极其全面的源，以供补充：http://italy.copybase.ch/blog/lista-repository- sourceslist-ottimizzata-per-ubuntu-kubuntu-linux/
# 保存编辑好的文件，执行以下命令更新。
保存编辑好的文件，执行以下命令更新。
sudo apt-get update
sudo apt-get dist-upgrade
ubuntu 10.04 更新源 sources.list
我也来凑凑人热闹,我是北京网通用戶,从网上搜集了很多,能用的不多,总结了下.
#uestc(成都市 电子科技大学更新服务器,推荐校园网和网通用户使用)
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
#网易
deb http://mirrors.163.com/ubuntu/ lucid main universe restricted multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid main universe restricted multiverse
deb http://mirrors.163.com/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-security universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-updates universe main multiverse restricted
#sjtu(上海交通大学更新服务器)
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
#SRT
deb http://ubuntu.srt.cn/ubuntu/ lucid main restricted universe multiverse
deb http://ubuntu.srt.cn/ubuntu/ lucid-security main restricted universe multiverse
deb http://ubuntu.srt.cn/ubuntu/ lucid-updates main restricted universe multiverse
deb http://ubuntu.srt.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb http://ubuntu.srt.cn/ubuntu/ lucid-backports main restricted universe multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid main restricted universe multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-security main restricted universe multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-updates main restricted universe multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-backports main restricted universe multiverse
#cn99
deb http://ubuntu.cn99.com/ubuntu/ lucid main multiverse restricted universe
deb http://ubuntu.cn99.com/ubuntu/ lucid-backports main multiverse restricted universe
deb http://ubuntu.cn99.com/ubuntu/ lucid-proposed main multiverse restricted universe
deb http://ubuntu.cn99.com/ubuntu/ lucid-security main multiverse restricted universe
deb http://ubuntu.cn99.com/ubuntu/ lucid-updates main multiverse restricted universe
deb-src http://ubuntu.cn99.com/ubuntu/ lucid main multiverse restricted universe
deb-src http://ubuntu.cn99.com/ubuntu/ lucid-backports main multiverse restricted universe
deb-src http://ubuntu.cn99.com/ubuntu/ lucid-proposed main multiverse restricted universe
deb-src http://ubuntu.cn99.com/ubuntu/ lucid-security main multiverse restricted universe
deb-src http://ubuntu.cn99.com/ubuntu/ lucid-updates main multiverse restricted universe