I am trying to integrate my application with Sagepay, using the Server Integration Protocol. I have written my code in JAVA and currently I am at the point where I'm sending a POST to Sagepay to be redirected to their payment page. However, I get a blank screen which is a result of an Error 400 (Bad Request).
In their documentation, they specifically state that:
The data should be sent as URL Encoded Name=Value pairs separated with & characters and sent to the Sage Pay Server URL with a Service name set to the message type in question.
What am I missing?
Thanks for your help!