Hi macom,
thank you for your help.
Uninstall the plugin from the GUI
then
apt-get purge minidlna
then install again from the GUI of OMV
......has brought no change.
Create the file 'minidlna.log' in '/ var / log /' and a ...
chown minidlna: minidlna /var/log/minidlna.log
Brought success.
Thanks orcape