Paypal web interface error

I am experiencing Paypal sandbox  connection problem ?
When ever I attempt to connect I receive the following error message.   

  Error During Web Interface. Error is: System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel.
            at System.Net.HttpWebRequest.GetRequestStream(TransportContext& context)
                   at(System.Net.HttpWebRequest.GetRequestStream())

I am operating Microsoft VS Express 2010 with Local server on laptop.

How does the changes effect my environment and how may I rectify problem encounter.