I just wanted to add a comment, for any others who come to this via Google.
I also hit this exact same error, but it turned out not to be caused directly by the network proxy. I had just run apt-add-repository, and that had failed to import the GPG key: root@buildhost:/home/mblokzij/ws-qvpc# add-apt-repository ppa:x2go/stable Quick howto to turn your machine into an X2Go server: ... gpg: keyring `/tmp/tmpf3fzey4y/secring.gpg' created gpg: keyring `/tmp/tmpf3fzey4y/pubring.gpg' created gpg: requesting key 0A53F9FD from hkp server keyserver.ubuntu.com gpgkeys: key A7D8D681B1C07FE41499323D7CDE3A860A53F9FD can't be retrieved gpg: no valid OpenPGP data found. gpg: Total number processed: 0 Note the last line. After manually importing the key, apt-get update ran fine. I used: apt-key adv --recv-keys --keyserver keys.gnupg.net 0A53F9FD I realise I used a different keyserver, but I copy/pasted the key id from the logs above. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1206824 Title: bogus network proxies might cause: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1206824/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
