How to remove RSA Key Pair from Smart Card

I was following Verify the Digital Signatures of XML Documents tutorial and got into trouble.

Now my smart card contains three additional key value pairs that are redundant a开发者_Go百科nd I have to remove them.

MSDN tutorial How to: Store Asymmetric Keys in a Key Container contains an explanation of how to remove the key from the container, but does not explain how to remove the existing keys.

When I re-start program that contains the following piece of code:

// Create a new CspParameters object to specify
// a key container.
CspParameters cspParams = new CspParameters(1, "ActivClient Cryptographic Service Provider");
cspParams.Flags = CspProviderFlags.UseDefaultKeyContainer;

// Create a new RSA signing key and save it in the container. 
RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider(cspParams);
rsaKey.PersistKeyInCsp = false;

Then the program will respond with the following error: The security token does not have storage space available for an additional container.

I am new to this (smart cards), so I'm totally lost. Please help.

---

that's because you have reached the limit of key containers that the card could host. This amount of maximal key containers can be obtained by querying the card minidriver (if present).