You have an unconventional smb.conf for sure - winbind references , You set it up to be a WINS server, SHARE level security instead of the default USER, and the path is in the [global] section for some reason:
winbind trusted domains only = Yes
idmap config * : backend = tdb
path = /media/MediaShare

read only = No
Anywho, What's the permissions of the target folder:
Code:
ls -dl /media/MediaShare