如何删除“忽略目录 /etc/apt/sources.list.d/ 中的文件，因为它具有无效的文件扩展名？

Question

自从将 13.10 升级到 14.04 后，我每次安装、更新、升级等时都会收到这些烦人的消息：

N: Ignoring file 'webupd8team-java-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension 
N: Ignoring file 'bumblebee-stable-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension 
N: Ignoring file 'steam.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'ubuntu-x-swat-x-updates-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'xorg-edgers-ppa-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'webupd8team-java-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'bumblebee-stable-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'steam.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'ubuntu-x-swat-x-updates-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'xorg-edgers-ppa-raring.list.disable' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension

如何解决消息中提到的潜在问题？

编辑：有时，我会收到附加到上述消息的其他消息：

W: GPG error: http://www.duinsoft.nl debs Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E18CE6625CB26B26
W: Failed to fetch http://ppa.launchpad.net/person/ppa/ubuntu/dists/karmic/main/binary-amd64/Packages  404  Not Found

W: Failed to fetch http://ppa.launchpad.net/person/ppa/ubuntu/dists/karmic/main/binary-i386/Packages  404  Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.

有时，我可能会遇到其他人，但我再也找不到确切的消息了。

Answer 1

要解决您的第一个问题，请在终端中运行它：

sudo rm /etc/apt/sources.list.d/*.disable

（当您禁用 PPA 时，旧版本的包管理工具会留下这些文件。删除它们非常安全）

您的第二个问题来自旧的 Karmic 存储库。要找出哪个在终端中运行它：

cd /etc/apt

grep -rw karmic *

一旦您知道它来自哪个存储库，就可以轻松禁用/删除它。