File Sharing Turns Off by itself

A problem has been occuring for a while now is that one of our machines (our server that is a site license administrator for Quark Express) somehow turns off it's file sharing. Is there any reason (other than a user) would make the file sharing turn off by itself?

I would run Repair Permissions via Disk Utility just in case, but it might be samba related as well (we had an issue at Corp with an older version of samba that seems similar)- try upgrading Samba.

Thank you for your reply. Where would I find the upgrade for samba. I do not want to get a bad download