Connecting a Mac Os X to a Windows file server

Hi,
I have a software on a Mac that has the license installed on a Windows
server. To use the software, I need to first access the license running on
the Windows server. But when I try to connect to the license on the
windows server from my mac, i get an error saying that the server is not
running when in fact it is.

Can someone give me some tips on how to overcome this??