Configuring Thin Client On Hp Proliant Server (ms Window 2003)

Have been working with thin client for some time now. I recently formatted my server and after loading all the necessary softwares, I found out that I can't access the server anymore from my thin client. Please, how do I configure the server/thin client to work as expected. However, they can ping each other and the thin clients can access the internet but can't access documents on the server.