Adding software sources
deb http://deb.torproject.org/torproject.org trusty main
W: GPG error: http://deb.torproject.org trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 74A941BA219EC810
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
deb.torproject.org-keyring
0 upgraded, 1 newly installed, 0 to remove and 93 not upgraded.
Need to get 5,268 B of archives.
After this operation, 7,168 B of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
deb.torproject.org-keyring
Install these packages without verification? [y/N] y
on ubuntu 14.04 lts