Test and live states

There are four possible states and responses for an order details submission:

State	Response
The details can be submitted to the live URL without the testMode parameter (or with the testMode parameter set to live mode - 0).	This is treated as a normal live submission.
The details can be submitted to the live URL with the testMode parameter set to test mode 100.	This causes a redirect page to open, with the following two outcomes: The redirect button is selected on the page and the submission is redirected to the test environment. The submission fails.
The details can be submitted to the test URL without the testMode parameter (or with the testMode parameter set to live mode - 0).	This generates an error.
The details can be submitted to the test URL with the testMode parameter set to test mode 100.	This is treated as a test submission in the test environment.