W:GPG error: http://us.archive.ubuntu.com precise Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>, W:GPG error: http://ppa.launchpad.net precise Release: The following signatures were invalid: BADSIG 175B884292C4BEFD Launchpad PPA for GNOME Split, W:Failed to fetch http://ppa.launchpad.net/openmetaverse/ppa/ubuntu/dists/precise/main/binary-i386/Packages  404  Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.