The request was aborted: Could not create SSL/TLS secure channel.System.Net.WebException

Question

I am using PayPalStandard plugin of NopCommerce. When I placed the order & make payment with paypalstandard plugin after successful payment on paypal, it redirects to mercha

Answer 1

I had the same issue connecting to sandbox(nvp), everything was fine then yesterday the message "The request was aborted: Could not create SSL/TLS secure channel." appeared.

I believe PayPal updated their endpoints on 19/20 January 2016 to use TSL 1.2 and HTTP 1.1.

To resolve this, for .NET 4.5 and above add the following line of code before calling WebRequest.Create().

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

Answer 2

The answer that worked for us was listed on the PayPal blog post, Upcoming Security Changes Notice. There are a number of things listed in the post, but the one thing which we did, and that worked, was PayPal SDK Updates. We updated using NuGet and everything started working again.