Hi, I think I followed http://www.debian.org/doc/manuals/securing-debian-howto/ch7.en.html paragraph 7.4.3 "Checking distribution releases" closely. When running apt-check-sigs I get * COULDN'T CHECK SIGNATURE BY KEYID: 2DB1C72530B34DD5 * NO VALID SIGNATURE This did not change after gpg --no-default-keyring --keyring trustedkeys.gpg --keyserver pgp.mit.edu --recv-keys 30B34DD5 Did I missed anything? Kind regards Andreas.