Enable GPG Mail on macOS Mojave or newer
On macOS Mojave or newer you need to enable the plug-in after installation. To enable GPG Mail please
- open Mail > Preferences > General > Manage Plug-Ins…
- tick checkbox for GPGMailLoader.mailbundle
- confirm with "Apply and Restart Mail"
After the restart GPG Mail will be loaded and Mail > Preferences > GPG Mail will show.