Note that a valid X.509 certificate from a trusted issuer is valid only for the use specified in the System.Security.Cryptography.X509Certificates.X509ChainPolicy object. Certificates that meet these chain policy rules might still be invalid for specific uses with such features as Security/MIME (SMIME), Authenticode, or Secure Sockets Layer (SSL). If further processing is required to determine whether the certificate is valid for a specific policy, derive a class from System.Security.Cryptography.X509Certificates.X509Chain and override the X509Chain.Build(X509Certificate2) method so that it calls the base class Build method first, and then does the additional processing.