NAV - Sharepoint integration

I,m new to this whole NAV, Sharepoint thing so i need some help. I’m supposed to integrate NAV to sharepoint so that i cn access NAV in sharepoint. I’ve been tryin to accomplish this using employee portal but whenever i try to install the NEP frontend i get the messege that i have not installed Sharepoint services. Please help past this hurdle. I’m using NAV 2009 and sharepoint 2010.