Samba is the standard Windows interoperability suite of programs for Linux and Unix.

https://www.samba.org/samba/

Check Samba is running

Optimize Samba

Resolve rlimit_max below minimum Windows limit

Samba Configuration

Samba Configuration Detailed

Samba Configuration Printer

Test nmbd

Test Samba’s ability to authenticate users

Verify Samba configuration settings

How can I log what files are accessed what is done with those files and by whom? You need to use at least samba-2.2.7a and use the audit.so module.

The samba source code has what you need. Check out the information in ~samba/examples/VFS/audit.c and in the README file in that directory.