SOLVED - Lost Permissions to one of my Plex media folders

[fdkin1]

All of a sudden I now have no access to my Plex music library using TrueNAS 13. Can access photos, Films, TV Programmes but not music. When I try selecting it on Windows 10 File Explorer I get the following message...
Windows cannot access \\TRUENAS\Plex Media\Music
You do not have permission to access \\TRUENAS\Plex Media\Music

Any help gratefully accepted.

 

[fdkin1]

Some further information...
I can access the Music folder on my android phone.
I can no longer access the Music folder on my PC
I can no longer access the Music folder on my Samsung TV
I can no longer access the Music folder via Sonos

 

[fdkin1]

Well I've solved it. I don't know how. Fiddled with the Plex dataset permissions in TrueNAS (inherit permissions and the option below it). Then save. Did this yesterday and it didn't work. Today it did. Doesn't explain how the permissions changed on one of the Plex media subfolders - the Music folder with all our personal music library stored. Perhaps through an upgrade? I don't know but it's now all working as it used to.
I'm running TrueNAS 13 u13.