Samba File sharing

ONe of our late programmer who is no longer working for us configured a SMB File Sharing but the problem is that for some reason it kicks us all off and in order for us to connect back we have to restart our computers (Only mac osx). Here are the details:

1. we are on DHCP
2. We are mac osx users that get boot off but windows has no problem reconnecting

A help would very much appreciated thank you.