I have an applicaton that uses SIM and Relay Responce.
It works perfect agaist the test server but when switched to the prod server, the Relay Responce does not seem to come back.
The merchant sit eis on a hosted server with no firewall issues.
I read another thread where the poster had a similar probelm and he saaid the fix was to use https on the x_relay_url
Is SSL required?
I thought one of the advantages for SIM was the merchant site did not require SSL.