title: setExpressCheckout and SSL/TLS error
body: <p>I'm  trying to develop a simple application that will enable users to purchase services off a website through the Paypal API. This application is running on ASP.NET with C#.</p>
  
  <p>I have had very little luck trying to get the Paypal API to co-operate. The method I'm calling is SetExpressCheckout with all the appropriate variables.</p>
  
  <p>I did my research and discovered that since I'm testing in Localhost, it may affect Paypal's ability to communicate with the application. So the next thing I tried was accessing my application through an open port and a publicly accessible IP address, but the same error occurs on the call to SetExpressCheckout.</p>
  
  <p>Here is the error:</p>
  
  <pre><code>Exception Details: System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel.
  
  Source Error: 
  
  
  Line 1790:        [return: System.Xml.Serialization.XmlElementAttribute("SetExpressCheckoutResponse", Namespace="urn:ebay:api:PayPalAPI")]
  Line 1791:        public SetExpressCheckoutResponseType SetExpressCheckout([System.Xml.Serialization.XmlElementAttribute(Namespace="urn:ebay:api:PayPalAPI")] SetExpressCheckoutReq SetExpressCheckoutReq) {
  Line 1792:            object[] results = this.Invoke("SetExpressCheckout", new object[] {
  Line 1793:                        SetExpressCheckoutReq});
  Line 1794:            return ((SetExpressCheckoutResponseType)(results[0]));
  
  Source File: c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\anan_p2\730602d6\31a8d74e\App_WebReferences.c8vgyrf8.2.cs    Line: 1792 
  </code></pre>
  
  <p>I've also tried generating certificates using OpenSSL and uploading them to the Paypal account's encrypted seller option but still no effect.</p>
  
  <p>Thank you very much for reading through my question!</p>
  
  <p>Update: As requested here is the code being used.</p>
  
  <pre><code>        String hostingOn = ConfigurationManager.AppSettings["default_site_url"];
          reqDetails.ReturnURL = hostingOn + "marketplace_confirm.aspx";
          reqDetails.CancelURL = hostingOn + "marketplace.aspx";
          reqDetails.NoShipping = "1";
          reqDetails.ReqConfirmShipping = "0";
  
          reqDetails.OrderTotal = new BasicAmountType()
          {
              currencyID = CurrencyCodeType.CAD,
              Value = payment_amt.Value,
          };
  
          SetExpressCheckoutReq req = new SetExpressCheckoutReq()
          {
              SetExpressCheckoutRequest = new SetExpressCheckoutRequestType()
              {
                  Version = UtilPayPalAPI.Version,
                  SetExpressCheckoutRequestDetails = reqDetails
              }
  
          };
  
          PayPalAPIAASoapBinding paypal = new PayPalAPIAASoapBinding();
  
          paypal.SetExpressCheckout(req);
  </code></pre>
  
  <p>I am also using the <a href="https://api-aa-3t.paypal.com/2.0/">https://api-aa-3t.paypal.com/2.0/</a> url for accessing the API</p>