موقع ری لود این اخطار رو داد
W: GPG error: http://archive.canonical.com lucid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5
W: GPG error: http://archive.ubuntu.com lucid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5
W: GPG error: http://archive.ubuntu.com lucid-updates Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5
W: GPG error: http://archive.ubuntu.com lucid-security Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5
W: GPG error: http://ppa.launchpad.net lucid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6AF0E1940624A220
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همیشه کلید مخازن رو نصب کن،نادیده بگیری میشی مثل من :-)