[polecat69]

Exakt så här står det i readme filen på kreditors modul

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STS FIX - For displaying error messages during the checkout process

Ian, Patrick, Deborah:

This fix should solve your problem with the credit class/gift voucher
contribution not displaying a coupon code error during checkout. I
just tried this code and it works great. You can thank Tom Thumb, who
used to frequent the STS forum. This STS fix should solve problems
with any contribution that is supposed to display error messages
during checkout (including Authroize.Net concolidated for AIM 1.7):

Look for this in includes/sts_display_output.php:

CODE
// Prepend any error/warning messages to $content
if ($messageStack->size('header') > 0) {
$template['content'] = $messageStack->output('header') . $template['content'];
}


Add this right after it:

CODE
////////Start Error Messages - Tom Wojcik
if (isset($HTTP_GET_VARS['error_message']) && tep_not_null($HTTP_GET_VARS['error_message'])) {
$messageStack->add('error_message', $HTTP_GET_VARS['error_message']);
$template['content'] = $messageStack->output('error_message') . $template['content'];
}
////// End Error Messages


Let me know if this works for you. I think this code would be worth
adding to the next version of STS.
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