当出现GPG的错误的时候，来这里

获取：56 http://security.ubuntu.com precise-security/main Translation-en [279 kB]                                                                                                                                  
获取：57 http://security.ubuntu.com precise-security/multiverse Translation-en [1,993 B]                                                                                                                           
获取：58 http://security.ubuntu.com precise-security/restricted Translation-en [2,805 B]                                                                                                                           
获取：59 http://security.ubuntu.com precise-security/universe Translation-en [91.9 kB]                                                                                                                             
下载 5,917 kB，耗时 1分 36秒 (61.3 kB/s)                                                                                                                                                                           
正在读取软件包列表... 完成
W: GPG 错误：http://ppa.launchpad.net precise Release: 由于没有公钥，无法验证下列签名： NO_PUBKEY EAA903E3A2F4C039
nice@lap2:~/xxx$ sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys EAA903E3A2F4C039
Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /tmp/tmp.XCAi9m9kOD --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv-keys EAA903E3A2F4C039
gpg: 下载密钥‘A2F4C039’，从 hkp 服务器 keyserver.ubuntu.com
gpg: 密钥 A2F4C039：公钥“Launchpad Subversion”已导入
gpg: 合计被处理的数量：1
gpg:               已导入：1  (RSA: 1)

sudo apt-get update

本文出自 “开源之星” 博客，请务必保留此出处http://kaiyuan.blog.51cto.com/930309/1904317

当出现GPG的错误的时候，来这里

原文：http://kaiyuan.blog.51cto.com/930309/1904317