CertX ActiveX.
Encryption ActiveX. Includes PKCS7, RSA, x509 and CSR. Created to be an equivalent for OpenSSL functions in PHP. CertX ActiveX is a component that uses the functions of OpenSSL for generation and verification of signatures and for sealing (encrypting) and opening (decrypting) data. It is fully compatible with PHP module. This can help you to develop web pages also on Windows platform with ASP and ASP.NET if you have an experience with PHP. Or on the contrary if you develop your encryption with this component you can easily port it to PHP/Unix with minimum efforts !

CertX ActiveX is the Shareware version. The full version can be purchased by clicking on the "CLICK HERE TO ORDER" button below for around 49.00USD.