我使用命令卸载了一个程序
sudo apt-get --purge remove programName
但当我运行 sudo apt-get update 时，它仍然返回该程序密钥的错误。因此，我使用以下命令卸载了该程序的密钥
sudo apt-key del AAAAAAAA
但随后我收到 sudo apt-get update 有关密钥的错误。具体来说，我试图完全删除 Epson 驱动程序，错误如下：
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://download.ebz.epson.net/dsc/op/stable/debian lsb3.2 Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E5E86C008AA65D56
W: Failed to fetch http://download.ebz.epson.net/dsc/op/stable/debian/dists/lsb3.2/Release.gpg The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E5E86C008AA65D56
W: Some index files failed to download. They have been ignored, or old ones used instead.
我只想删除有关这些 Epson 驱动程序的所有内容，这样我每次运行更新时就不会再为此烦恼。