1.- you’ve had to execute this step in order.,
2.- did you extrat it first…?
3.- First extract, this expand the Directory in your home…
tar xf net.downloadhelper.coapp-1.5.0-1_amd64.tar.gz -C ~
4.- Then, execute from your home:
~/net.downloadhelper.coapp-1.5.0/bin/net.downloadhelper.coapp-linux-64 install --user
Output
VdhCoApp: VdhCoApp is ready to be used
5.- Open Downloaderhelper, click on preferences and expand Auxiliar Aplication installed:
Found Aplication Auxiliar AplicaTión: *VdhCoApp 1.5.0*
Root Aplication: */usr/local/net.downloadhelper.coapp-1.5.0/bin/net.downloadhelper.coapp-linux-64*
6.- It doesn’t find click on → re-check
Regards.,