Does there exist an option to refresh the guide more often or at another time during the day?
In days like these, very often there are special broadcasts added to the schedule on short notice shifting the start times in the evening. The Plex DVR won’t recognise this if one does not run a manual update of the guide during the day.
But, when issuing the above curl command, or trying to access the same link from a browser, I do get a “404 Not Found” error.
Any idea as to why this is failing?
When testing with curl, try enclosing the URL in double-quotes: curl -X POST "http://<IP_OF_PMS>:32400/livetv/dvrs/<DVR_KEY_FROM_ABOVE>/reloadGuide?X-Plex-Token=XXYYZZ"
And, of course, ensure you replace ‘XXYYZZ’ with your actual Plex token.