Do you want to temporarily store the customer's card details in the session? (They'll be cleared from the session when the order is completed). <br /><br />When this option is enabled, if a customer makes a mistake when entering their details, the module will restore the details entered so they don't have to re-enter them. For security reasons, it is advised that these details are encrypted (which requires the PEAR:Crypt_Blowfish package to be installed <strong>and accessible</strong> on the server).<br /><br />When this option is disabled, and a problem is encountered with the card details entered by the customer, none of the details entered by them will have been stored, so they'll have to enter all the details again. In this case, since details will have not been stored in the session, Blowfish Encryption won't be necessary.