Check the Version of gpgmepp. I had version 16.08.3-1. The newer version is 2.0.0-2. But pacman thinks this version is older. You can see this in Octopi and also install version 2.0.0-2.
See here: https://bbs.archlinux.org/viewtopic.php?id=306100
My problem was this:
https://forum.manjaro.org/t/libreoffice-startet-nach-update-nicht-mehr/179577/9