如何在更新时修复下载问题?

可能重复:
如何使用PPA修复404错误?

出于某种原因,每次我尝试通过终端,synaptic和更新管理器更新时,我收到此错误消息,我无法更新所需的所有数据。

W:Failed to fetch cdrom://Ubuntu-Netbook 10.04 _Lucid Lynx_ - Release i386 (20100429.4)/dists/lucid/main/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs , W:Failed to fetch cdrom://Ubuntu-Netbook 10.04 _Lucid Lynx_ - Release i386 (20100429.4)/dists/lucid/restricted/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs , W:Failed to fetch http://ppa.launchpad.net/canonical-dx-team/une/ubuntu/dists/natty/main/source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/canonical-dx-team/une/ubuntu/dists/natty/main/binary-i386/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/lorenzo-carbonell/atareao/ubuntu/dists/natty/main/source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/lorenzo-carbonell/atareao/ubuntu/dists/natty/main/binary-i386/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/meebey/ppa/ubuntu/dists/maverick/main/binary-i386/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/team-xbmc/ppa/ubuntu/dists/natty/main/source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/team-xbmc/ppa/ubuntu/dists/natty/main/binary-i386/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/ubuntu-desktop/gnome3-builds/ubuntu/dists/natty/main/source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/ubuntu-desktop/gnome3-builds/ubuntu/dists/natty/main/binary-i386/Packages 404 Not Found , E:Some index files failed to download. They have been ignored, or old ones used instead. 

使用Update Manager单击“设置”按钮。 这将打开您的软件源窗口:

  1. 解开“CD-ROM”选项 – 在我的例子中它是“Ubuntu 10.10”
  2. 浏览列表并取消所有PPA
  3. 然后单击关闭
  4. 检查您现在是否可以成功更新。

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如果仍然无法更新,请将下载镜像更改为其他服务器: 在此处输入图像描述] [2