Parameter Error is displayed upon payment with 2CheckOut

Question:

Parameter Error is displayed upon payment with 2CheckOut

Answer:

This indicates that your seller ID or secret key are incorrect. Please make sure your seller ID is as shown in your 2CheckOut account, and double-check that your secret key is correct and that you've not accidentally entered your 2CheckOut account password instead. Your secret key is configured on the "Look and Feel" page of your 2CheckOut account.