I am working on a solution that needs to decrypt PKCS#7 encrypted data, preferably in C#. As far as I can see, the .NET api has support for this through the System.Security.
.Net Framework from 2.0 provided pkcs namespace that helps us to do sign/encrypt/decrypt in pkcs#7 standard. Please refer here for the overview http://msdn.microsoft.com/en-us/library/bb885086.aspx and here for a good example http:**msdn.microsoft.com/en-us/library/bb924565.aspx.