user permissions not working - must be a config error

Maybe I am making this more complicated than it needs to be - I suppose that can be said often for security.

Anyway - I have a series of directories that I can browse from the command line using Putty but using the same user ids from a Win10 box I can't access the same shares via Samba. What am I doing wrong?

Here is the directory on the Ubuntu Server:

drwxrwxr-x 201 jenny g-dlna 204 Jul 16 10:14 Music
drwxrwx--- 9 jenny g-adults 34 Jul 19 15:05 OurDocs
drwxrwx--- 2 ken g-adults 3 Aug 21 22:23 Test

If I chmod 777 the directory then the shares work - what the freak??? Is group permissions not working in Samba?

What I am running:
Samba version 4.3.9-Ubuntu for the server

Windows 10 on the client

It's got to be error 12 (12 inches from my screen i.e. user error!!)