I am developing an application that update the profile of a user
(using the Profile Object Model). I am developing on VS.NET 2003 on
an XP machine, with SPS installed on W2K3.

From the SDK:

TopologyManager topology = new TopologyManager();
PortalSite portal = topology.PortalSites[new Uri("portalURL")];
PortalContext context = PortalApplication.GetContext(portal);
UserProfileManager m_mngr = new UserProfileManager( context );
UserProfile user = m_mngr.GetUserProfile("WindowsUseraccount");

Console.WriteLine("Property to be changed : " + sProperty + " to " +
sValue.ToString() );
user[sProperty] = sValue;
u.Commit();

But on compiling, I got an error stating that the references to the
Sharepoint.Security could not be found. After obtaining the
necessary DLLs from the SPS server (as detailed at :
http://www.sharepointu.com/forums/HELP!_I_need_Microsoft%
25Sharepoint%25dll_!!!/m_8713/tm.htm )
I now get this error:

"Sharepoint Product registry key not found"

What am I missing?