I posted this earlier today in the Mac forum, I'm guessing I posted it in the wrong place. Not sure how to move a topic, so I hope it's OK to re-post it in here.
Anyway... back to the matter at hand.
All of a sudden my TV Shows and Movies stopped pulling any metadata. Everything was working fine last week.
I went to check Settings -> Server -> Agents... but each section was blank; no options. [See attachment #1]
Occasionally, some options would load after about 5 minutes of waiting. But even when I selected them nothing would happen. It would revert back to no agents being selected as soon as I moved away from that page.
I checked the error console in Safari and it is full of 404 Not Found errors for all of the agents. [See attachment #2]
I'm having a similar issue, however i am able to see the agents, just is unable to find any matches, even in custom search (and it is on their website)
I'm having the exact same issue after upgrading Plex on my Synology to 0.9.9.10. No metadata agents available. I have previously added a custom agent for scanning blueray iso files, but I'm not sure if this is related or not.
EDIT: Managed to solve this just by rebooting the PMS. Updated the custom agent as well just for good measure (https://support.plex.tv/hc/en-us/articles/201674343-Scanning-Disk-Image-Format-Media). I still only see one agent under /volume1/Plex/Library/Application Support/Plex Media Server/Scanners, but I guess it's supposed to be like that :p