Add warning for transcoding temporary path permissions

[JamesD27 2]

Hiya,

Long story short, I spent a long time figuring out why transcoding wasn't working, from originally using emby in a container on a VM with iGPU passthrough, to various versions of Ubuntu, to eventually putting it on Ubuntu bare metal. I tried everything to get transcoding working, and had no luck

Eventually I wondered about the Transcoding temporary path, which by default had nothing in it (so as to use the default unknown folder). I created a folder, gave it every permission for the emby user, then plugged that in to the path and now transcoding works flawlessly.

Default setting, no path, transcoding doesnt work, no warning

New path, transcoding works fine

My request is to have some kind of obvious warning if there's an issue with the path chosen by Emby by default. There is a warning if you enter a new path and set it, but unless you do that, you wont know. Maybe a warning saying "unable to access path" to prompt the user to find and fix the problem

[Luke 42077]

Hi, if there was a problem with the server's default transcoding temp path when you had the field blank, then you probably have bigger issues then just that. That lives underneath the server's data folder, so if it cant' write to that, then its' going to cause other problems as well. 

When you try and customize the path, the server will alert you if you enter an invalid path. Does that help answer your question?