Problem integrating crystal report with SharePoint 2007

Good evening,
I am trying integration of Microsoft SharePoint Portal Service 2007 with Crystal Reports, so that I can directly view the report within the portal.
Whenever I try to install Microsoft SharePoint 2007 Portal Integration Kit for Business Objects XI 3.1, the installation failed giving me the following error.
Error:
Fatal Error
Installation ended prematurely because of an error.
Installer Information
The enterprise .Net SDK feature of business Objects Enterprise XI 3.1 must be installed before installing this software.
I try to find everywhere on the Microsoft forums and in the Google, but wasn’t succeeded in locating it. If anyone of you know how to solve this problem, do tell me. I’ll be very thankful to you.
My hardware is Intel Core i7 processor with 4 GB of RAM and Windows Server 2003 Service Pack 2. SharePoint Portal Server 2007.
Thanks.
