there are two definitions for ERROR_REDEEMED_AMOUNT_ZERO that comes up when a valid coupon number is added, but the restrictions(i.e. uses, expiration date, etc.) prevent it from being used.

the two are defined in:
catalog/includes/languages/english/add_ccgvdc_english.php
catalog/includes/languages/english/modules/order_total/ot_coupon.php

And called for in catalog/includes/modules/order_total/ot_coupon.php

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1. *** catalog/includes/languages/english/add_ccgvdc_english.php ***
REMOVE OR COMMENT:
define('ERROR_REDEEMED_AMOUNT_ZERO', '
***HOWEVER:No reduction available, please see the coupon restrictions***');


2. *** catalog/includes/languages/english/modules/order_total/ot_coupon.php ***
CHANGE:
define('ERROR_REDEEMED_AMOUNT_ZERO', 'a valid coupon number. HOWEVER: No reduction will be applied, please see the coupon restrictions that was sent within your offer email**');

TO:
define('ERROR_REDEEMED_AMOUNT_ZERO', '*** This is a valid coupon code. HOWEVER: No price reduction can be applied, please see the coupon restrictions that were sent with your email offer. **');


3. *** in catalog/includes/modules/order_total/ot_coupon.php ***

CHANGE:
if ( strlen($cc_id)>0 && $coupon_amount==0 ) {
$err_msg = ERROR_REDEEMED_AMOUNT.ERROR_REDEEMED_AMOUNT_ZERO;
} else {
$err_msg = ERROR_REDEEMED_AMOUNT.$coupon_amount_out;
}
tep_redirect(tep_href_link(FILENAME_CHECKOUT_PAYME NT, 'payment_error='.$this->code.'&error=' . urlencode($err_msg), 'SSL'));

TO:
//lildog ccgv coupon restrictions error fix
if ( strlen($cc_id)>0 && $coupon_amount==0 ) {
// $err_msg = ERROR_REDEEMED_AMOUNT.ERROR_REDEEMED_AMOUNT_ZERO;
$err_msg = ERROR_REDEEMED_AMOUNT_ZERO;
} else {
$err_msg = ERROR_REDEEMED_AMOUNT.$coupon_amount_out;
}
tep_redirect(tep_href_link(FILENAME_CHECKOUT_PAYME NT, 'payment_error='.$this->code.'&error=' . urlencode($err_msg), 'SSL'));



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