GPG error: http://extras.ubuntu.com trusty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY F60F4B3D7FA2AF80

今天在更新运行apt-get update的时候出现了如下的错误:

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 F60F4B3D7FA2AF80

解决方法：

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F60F4B3D7FA2AF80