以编程方式使用私钥导入证书

I'm trying to use the HttpListener class in a C# application to have a mini webserver serve content over SSL. In order to do this I need to use the httpcfg tool. I have a .pfx file with my public and private key pair. If I import this key pair manually using mmc into the local machine store, everything works fine. However, if I import this key pair programmatically using the X509Store class, I am not able to connect to my mini webserver. Note that in both methods the cert is getting imported to the MY store in LocalMachine. Oddly, I am able to view the certificate in mmc once I programmatically import it and when I view it, the UI indicates that a private key is also available for this certificate.I'm trying to use the HttpListener class in a C