if using .Net as your programming platform, you may need to force it to use TLS 1.2 C# using System.Net;
// force legacy PayFlow Pro SDK DLL to use TLS 1.2
System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; VB.Net Imports System.Net
' --- force legacy PayFlow Pro SDK DLL to use TLS 1.2
System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12
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