从7.10想升级到8.04版本，出现如下错误：

xgx@xgx-laptop:/etc$ do-release-upgrade
Checking for a new ubuntu release
Done Upgrade tool signature
Done Upgrade tool s .1
Done downloading
extracting '/tmp/tmpp7rica/hardy.tar.gz'
authenticate '/tmp/tmpp7rica/hardy.tar.gz' against '/tmp/tmpp7rica/hardy.tar.gz.gpg'

正在读取缓存

正在检查软件包管理器
Reading package lists: Done
Reading state information: DoneReading state information: Done
Reading state information: Done
Ignored cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy Release.gpg
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy Release.gpg
Ignored cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy Release
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy Release
Ignored cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/main Packages
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/main Packages
Ignored cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/restricted Packages
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/restricted Packages
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/main Packages
Failed cdrom://Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016) gutsy/restricted Packages
Done downloading
Reading package lists: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done

更新源的信息
Done http://archive.ubuntu.com hardy Release.gpg
Hit http://archive.ubuntu.com hardy Release
Done http://archive.ubuntu.com hardy Release
Hit http://archive.ubuntu.com hardy/main Packages
Done downloading

正在检查软件包管理器
Reading package lists: Doneardy/main Packages: 84
Reading state information: Done
Reading state information: Done
Reading state information: Done

正在计算改变

未能计算更新

在筹划升级时，一个不可解决问题发生了：

这可能是由以下原因造成的：
*升级为Ubuntu的未发布版本
*运行目前的Ubuntu未发布版本
*不是由Ubuntu提供的非官方软件包

如果没有一个被应用，那么请报告本 'update-manager'
包的错误，在报告中包含 /var/log/dist-upgrade/
中的文件。


正在恢复原始系统状态

中止
Reading package lists: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done
xgx@xgx-laptop:/etc$

换了一些源错误仍在，望高人指点，谢谢！

who knows?

我也不知道是什么原因，我这里也出现了！希望有知道的朋友帮助一下！

我的也是 更新里有一个文件下载后安装出错了

一直没有人解决这个问题，希望有大侠帮助一下，本人严重等待中！