RSA Key container was not found - ERROR

Hi,
I am trying to use the RSAProtectedConfiguraionProvider to encrypt sections of my web.config file.  In my test environment (win 2000) if I do the following command aspnet_regiis -pa "NetFrameworkConfigurationKey" "ASPNET" it runs successfully, and then I can encrypt and decrypt as required.  
 
The problem:
In my Production environment (win 2000) it returns an error "RSA Key Container was not found" If I take a look in the machine.config file I do see it there.
Any ideas.
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