Issue

• Why can't the public key created on Red Hat Enterprise Linux 6 machine encrypt file on Red Hat Enterprise Linux 7 and generate error "gpg2 encryption of fileXYZ failed Unusable public key" ?

[root@localhost ~]# gpg2 --list-keys
/root/.gnupg/pubring.gpg
------------------------
pub      0s/E7717893 2016-01-20
uid                  TraxPROD

[root@localhost ~]# gpg2 -r test --encrypt-files anaconda-ks.cfg 
gpg: test: skipped: Unusable public key
gpg: encryption of `anaconda-ks.cfg' failed: Unusable public key

• Even after adding trust-always policy, it doesn't work

[root@rhel7 ~]# gpg2 -r test  --trust-model always --encrypt-files anaconda-ks.cfg
gpg: test: skipped: Unusable public key
gpg: encryption of `anaconda-ks.cfg' failed: Unusable public key