我在 HP Pavilion dv7 笔记本电脑上使用 Ubuntu 14.04 LTS-64。昨天我添加了一个存储库，当我执行“sudo apt-get update”时，我收到了以下消息：
W: GPG error: http://archive.canonical.com trusty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 NO_PUBKEY 3B4FE6ACC0B21F32
W: GPG error: http://extras.ubuntu.com trusty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 16126D3A3E5C1192
W: GPG error: http://mirror.symnds.com trusty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 NO_PUBKEY 3B4FE6ACC0B21F32
W: GPG error: http://mirror.symnds.com trusty-updates Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 NO_PUBKEY 3B4FE6ACC0B21F32
W: GPG error: http://mirror.symnds.com trusty-backports Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 NO_PUBKEY 3B4FE6ACC0B21F32
W: GPG error: http://mirror.symnds.com trusty-security Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 NO_PUBKEY 3B4FE6ACC0B21F32
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我尝试过“sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys”，但无法解决问题。我取消勾选所有存储库，重新更新，消息相同。我重新启动，问题仍未解决，消息相同。
当我执行“sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys”命令时，我在终端上看到的内容如下：
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 40976EAF437D05B5
[sudo] password for brwright:
Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --homedir /tmp/tmp.xYr7arweRj --no-auto-check-trustdb --trust-model always --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyring /etc/apt/trusted.gpg.d/aking1012-com-lenstoggle.gpg --keyring /etc/apt/trusted.gpg.d/alessandro-strada-ppa.gpg --keyring /etc/apt/trusted.gpg.d/alexx2000-doublecmd.gpg --keyring /etc/apt/trusted.gpg.d/amith-ubuntutools.gpg --keyring /etc/apt/trusted.gpg.d/antono-shelr.gpg --keyring /etc/apt/trusted.gpg.d/appgrid-stable.gpg --keyring /etc/apt/trusted.gpg.d/apt-fast-stable.gpg --keyring /etc/apt/trusted.gpg.d/arctica0316-ppa.gpg --keyring /etc/apt/trusted.gpg.d/askubuntu-tools-ppa.gpg --keyring /etc/apt/trusted.gpg.d/atareao-atareao.gpg --keyring /etc/apt/trusted.gpg.d/atareao-lenses.gpg --keyring /etc/apt/trusted.gpg.d/atareao-nautilus-extensions.gpg --keyring /etc/apt/trusted.gpg.d/banshee-team-banshee-daily.gpg --keyring /etc/apt/trusted.gpg.d/banshee-team-ppa.gpg --keyring /etc/apt/trusted.gpg.d/bhdouglass-indicator-remindor.gpg --keyring /etc/apt/trusted.gpg.d/bridge-daily.gpg --keyring /etc/apt/trusted.gpg.d/caffeine-developers-ppa.gpg --keyring /etc/apt/trusted.gpg.d/cairo-dock-team-ppa.gpg --keyring /etc/apt/trusted.gpg.d/cairo-dock-team-weekly.gpg --keyring /etc/apt/trusted.gpg.d/caldas-lopes-ppa.gpg --keyring /etc/apt/trusted.gpg.d/cdekter-ppa.gpg --keyring /etc/apt/trusted.gpg.d/chris-lea-node_js-legacy.gpg --keyring /etc/apt/trusted.gpg.d/claudiocn-slm.gpg --keyring /etc/apt/trusted.gpg.d/cooperjona-nitrotasks.gpg --keyring /etc/apt/trusted.gpg.d/costales-folder-color.gpg --keyring /etc/apt/trusted.gpg.d/costales-unity-webapps-telegram.gpg --keyring /etc/apt/trusted.gpg.d/danielrichter2007-grub-customizer.gpg --keyring /etc/apt/trusted.gpg.d/deja-dup-team-testing.gpg --keyring /etc/apt/trusted.gpg.d/diesch-testing.gpg --keyring /etc/apt/trusted.gpg.d/dlech-keepass2-plugins.gpg --keyring /etc/apt/trusted.gpg.d/dr3mro-personal.gpg --keyring /etc/apt/trusted.gpg.d/ehoover-compholio.gpg --keyring /etc/apt/trusted.gpg.d/flozz-flozz.gpg --keyring /etc/apt/trusted.gpg.d/format-junkie-team-release.gpg --keyring /etc/apt/trusted.gpg.d/fossfreedom-indicator-sysmonitor.gpg --keyring /etc/apt/trusted.gpg.d/freyja-dev-unity-tweak-tool-daily.gpg --keyring /etc/apt/trusted.gpg.d/gencfsm-ppa.gpg --keyring /etc/apt/trusted.gpg.d/george-edison55-nitroshare.gpg --keyring /etc/apt/trusted.gpg.d/n-muench-burg.gpg --keyring /etc/apt/trusted.gpg.d/rednotebook-daily.gpg --keyring /etc/apt/trusted.gpg.d/webupd8team-y-ppa-manager.gpg --keyserver keyserver.ubuntu.com --recv-keys 40976EAF437D05B5
gpg: keyblock resource `/etc/apt/trusted.gpg.d/n-muench-burg.gpg': resource limit
gpg: keyblock resource `/etc/apt/trusted.gpg.d/rednotebook-daily.gpg': resource limit
gpg: keyblock resource `/etc/apt/trusted.gpg.d/webupd8team-y-ppa-manager.gpg': resource limit
gpg: requesting key 437D05B5 from hkp server keyserver.ubuntu.com
gpg: key 437D05B5: "Ubuntu Archive Automatic Signing Key <[email protected]>" 26 new signatures
gpg: Total number processed: 1
gpg: new signatures: 26
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我该怎么办？我怎么把这事搞砸了？任何帮助都将不胜感激。操作系统似乎运行良好，重启时没有问题，也可以正常使用操作系统。有什么线索吗？
答案1
对于所有错误，请尝试“sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys ”命令，例如：
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 16126D3A3E5C1192