One last query Marius, did you specify a prefix when installing gpoweroff? I've just done an install in a VM and by default it installs to /usr/bin/gpower, rather than /usr/local/bin/gpoweroff as your error shows the location to be. This is what is causing the issue you're experiencing.
One last query Marius, did you specify a prefix when installing gpoweroff? I've just done an install in a VM and by default it installs to /usr/bin/gpower, rather than /usr/local/ bin/gpoweroff as your error shows the location to be. This is what is causing the issue you're experiencing.