Quote Originally Posted by diannev View Post
I'm also getting that error message...

Warning: Missing argument 2 for zen_add_tax() in ../zencart/includes/functions/functions_taxes.php on line 94

Line 94 reads (along with comment above):
////
// Add tax to a products price based on whether we are displaying tax "in" the price
function zen_add_tax($price, $tax) {

It is fine on Amounts, just not percentages.

Is there anyone smart enough out there to compare the Amount vs Percentage calculations and perhaps spot the error? Its probably in ordertotal/ot_insurance.php between lines 165 and 173.
I don't get this error. Make sure that even though you're using percentage, have values in the rate, increment amount, etc... meaning leave nothing blank.