BPC MS 7.5 client instal

Hi   Im installing BPC MS 7.5 for the first itme - in the inst guide for the client is written this " ponit to http;//<PC_server:port/osoft"

I'm trying to install on same server as the BPC serverpart and wrote  http://dkmidbpc01:80/osoft but only got an emty screen back with HTTP 404 Not found ! 

dkmidbpc01  is the name of the server

I do not have any idea how to fix this!

BR

Niels R.