CAPICOM has finally been deprecated, and it won't be supported on Windows 7. This link is up to date and proposes alternatives to CAPICOM classes by using .NET classes and CryptoAPI: Alternatives to Using CAPICOM.
The following article may help if you were using CAPICOM in your web site and you are planning on using .NET now: Writing an ActiveX Control in .NET.
I hope this helps.
Alex (Alejandro Campos Magencio)