NAS Netgear 316 - Firmware 3.5.1 - Plex Media Server

After firmware-Reset and update the Firmware to 3.5.1. - Plex Media Server not in the APP-List (installed or/and available).
Download plexmediaserver-ros6-binaries_1.0.3.2461-35f0caa_amd64.deb from plex.tv.
Upload to NAS Netgear 316 (Intel).
Error: Can not install application.

I hope, i become help.
Thanks.