For Phpauction to be able to process payment through your 2checkout account you must properly configure the credit card settings following the steps below:

• Go to 2checkout.com
• Log in into your account
• Select Shopping Cart > Cart details
• In the Shopping Cart Parameters page set
  • Return to a routine on your site after credit card process to yes
  • In the Return URL field enter the complete URL to 2checkoutipn.php on your site. I.e., if your Phpauction installation is at http://www.yoursite.com enter http://www.yoursite.com/2checkoutipn.php
• Click on the save changes button