I am a Plex Pass Subscriber and use this mostly for the trailers. I cannot tell you exactly when it started, but movies appear to have a trailer available, but the trailer never loads. I suspect something in the server updates, but I can’t be specific as to when it was working last, only that it used to work flawlessly. These are not locally stored trailers. Movies and other local content play without a problem in all scenarios. The web client simply returns to the movie detail screen, and the Media Player gives a general “Conversion Failed. The transcoder exited due to an error” error. This is occurring both locally with Media Player and Web Client as well as with remote access. I have made sure both server and client are up to date (Server v1.13.2.5154, Web v3.59.1, MP v2.13.0.877-6e1ea2cb).
I have cleared the cache, optimized db, cleaned bundles, emptied trash, and restarted both the server and the machine running the server (Windows 10), as well as refreshed metadata after all of the above.