VIdeo Library Thumbnails Not Correct

[flibberflops 1]

It did look like the attached photos (only 3 films inside "movies" but the thumbs were showing films that were deleted moths ago). However, I think I may have finally fixed it....

Did a backup of the embyserver 

Uninstalled the embyserver and ensured both @appstore and @appdata /EmbyServer folders (synology) was deleted.

Reinstalled  embyserver and performed a restore.

Interestingly when I first did the restore, the thumbs did still show wrong again (exactly as before) but after a fresh scan of library files, it corrected them and so far it has been many hours and they still are correct (previously a scan corrected them but they reverted back only after an hour)