Plex Media Server Not Authorized

My Cloud OS 5 Personal & Network Attached Storage My Cloud EX Series
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1

Plex Media Server when launched from My Cloud Device login page → Installed Apps → PMS Configure always throws an error “Not Authorized, you do not have access to this server”

PMS version: 1.26.2.5797
MyCloudOS5 EX2 Ultra firmware: 5.26.300

http://172.168.1.121:32400/web/index.html#!/setup/061430a534c52f2268687d13f5d87d3050616481

2

Try to install new version on NAS https://downloads.plex.tv/plex-media-server-new/1.32.5.7328-2632c9d3a/wd/PlexMediaServer-1.32.5.7328-2632c9d3a-MyCloudEX2Ultra_OS5.bin