This is what appears to resolve my connectivity problem, in my code.
Updated the underlying .NET Framework to 4.6.1 (works with 4.5.2, as
well) and prior to interacting with the AuthorizeNet service, I tell the
ServicePointManager explicitly to use T...
Hello, Jarrod - Would you mind explaining what it was, exactly, that
fixed your issue? We're seeing the same thing and I'm curious what
resolved your issue. Thank you - Gary