c# - PayGate PayXML integration using asp.net throws "Authentication failed because the remote party has closed the transport stream" -

how integrate paygate payment gateway's paygate payxml asp.net using c# or vb. when run sample application given paygate developer login got error "authentication failed because remote party has closed transport stream." hope expert forum me. in advance.

i received error trying integrate payweb module using .net framework 4.0. created simple webrequest post https://secure.paygate.co.za/payweb3/initiate.trans , receive "authentication failed because remote party has closed transport stream." error.

all stackoverflow posts error pointed tls1 problem .net 4.0 activating tls1.1 , tls1.2 on hosting server didn't fix issue. changing exceptions on firewall did not resolve error. paygate had no idea how fix error, after 60 emails , forth.

in end upgraded .net 4.5.2 on server fixed problem.