Big Thank you to you both - grateful for the advice - the job is now done
Observation -
going through by folders (as I did), no need to add tracks to the library but a relatively slow job going through hundreds of folders (unless I have missed something).
Adding all files, then looking at "All Tracks" date added, would perhaps have been quicker, but I think I would have not noticed some tracks that were not in the Library, and should have been.
Thanks again

[quote=MalcoD post_id=517678 time=1709840179 user_id=120241]
I have 11,400 files in the MMW Library, but 14,400 in the Folder on the Computer. The 3,000 difference are duplicates that I have removed from the Library.
Is there a way to identify those 3,000 files so I can move them from the Folder.
[/quote]

Riffing off what Lowlander suggested:

If you open the Folders node, you are looking at your disk folders, not your MM database.
If you included the Added column in your display and sort by that column, you will be able to identify tracks that are not in your MM database because they will have no Added value. ... The Added column shows the date when a track was added to the MM database.

There is no need to scan the duplicate tracks into the MM database, as suggested by Lowlander.

No, but if you were to scan the folder, sort on Added in MediaMonkey, you could remove these files (from both Library and PC).

I have 11,400 files in the MMW Library, but 14,400 in the Folder on the Computer. The 3,000 difference are duplicates that I have removed from the Library.
Is there a way to identify those 3,000 files so I can move them from the Folder.