IIS backward compatibility components were not detected
Upgrade Advisor did not detect IIS components and settings that provide information used by Setup to create new Reporting Services URLS.
After upgrade finishes, use the Reporting Services Configuration tool to set the URLs for report server or Report Manager. Use IIS Manager to remove the virtual directories you no longer need.
For more information, search for "How to: Configure a URL (Reporting Services)" in SQL Server Books Online.