"The specified cryptographic algorithm is not supported on this platform" error when using ECDiffieHellmanCng on windows server 2003

I am following the steps from MSDN for Cryptography Next Generation (CNG) Secure Communication Example. I can build the 3 solutions with no problem (Alice,Mallory,Bob) but when I try to run them I get the following error "The specified cryptographic algorithm is not supported on this platform". According to the documetation ECDiffieHellmanCng Class is supported on win server 2003. I have framework 3.5 installed. As I said all solutions compile with no problem. I am running Windows Server 2003 with SP2.  Any information will be greatly appreciated.

 

Thanks
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