"Object was not found" exception thrown when calling System.Security.Cryptography.CngKey.Create

Hi,

I'm running a WPF service on Windows Server 2008 SP2 with IIS 7.5 and when I try to call the CNGKey.Create API I am getting the following exception thrown:

System.Security.Cryptography.CryptographicException: Object was not found.
   at System.Security.Cryptography.CngKey.Create(CngAlgorithm algorithm, String keyName, CngKeyCreationParameters creationParameters)

This error only occurs when I'm running the actual service through IIS.  When I run through Visual Studio with F5, this code works just fine.  Any ideas on what is causing this issue or how to resolve my server setup?