Hi there
On previous builds of Windows I was getting strange mappings on the "C" drive from SAMBA - it was only showing Boot and missing the rest of the directory. Other drives were fine ???!!

Clean install on build 10074 seems to have fixed the problem of Samba shares. W10 access also from the Linux system fine too now. W7 / XP ==>W10 and W10==>W7/XP (i.e both ways) works fine as well.

(Linux -- Centos rel 7 -- no recent updates done on this system).

No need to reset / fiddle around with ports in firewall.

Looks like build 10074 is turning out just OK --but CLEAN install seems to be required --update from 10061 gave all sorts of weird problems.