我正在运行 16.04 LTS，并出现“下载包文件失败”的提示。（免费翻译，我的发行版是葡萄牙语的）。
我试过了这解决方案，但每当我单击“确定”时，它都会要求我重新加载。然后，当它尝试重新加载时，它再次失败并出现相同的错误。
这是输出错误：
W:An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://repository.spotify.com stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY EFDC8610341D9410, W:https://content.runescape.com/downloads/ubuntu/dists/trusty/InRelease: Signature by key AAC9264309E4D717441DB9527373B12CE03BEB4B uses weak digest algorithm (SHA1), W:The repository 'http://ppa.launchpad.net/osmoma/audio-recorder/ubuntu xenial Release' does not have a Release file., W:Data from such a repository can't be authenticated and is therefore potentially dangerous to use., W:See apt-secure(8) manpage for repository creation and user configuration details., W:Failed to fetch http://repository.spotify.com/dists/stable/InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY EFDC8610341D9410, E:Failed to fetch http://ppa.launchpad.net/osmoma/audio-recorder/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found, W:Some index files failed to download. They have been ignored, or old ones used instead.
我需要一些帮助，因为我需要更新一些文件并为四月份的升级做准备。