ZC Version: 1.5.4c (downloaded and upgraded from the Zen-Cart Site using the recommended procedure of running a duplicate site)
PHP Version: 5.4.45

I am having problems with some orders not being completed when customer uses the Authroize.net (SIM) payment module. The issue is likely caused by the samesite cookie rule that Chrome introduced.

As suggested in other threads https://www.zen-cart.com/showthread....light=samesite

I added
/includes/extra_datafiles/set_samesite_cookie.php

containing
PHP Code:
<?php
define
('COOKIE_SAMESITE''none');
and since I am using v154 that doesn't have the COOKIE_SAMESITE defined I modified
includes/init_includes/init_sessions.php

$samesite = (defined('COOKIE_SAMESITE')) ? COOKIE_SAMESITE : 'lax';
if (!in_array($samesite, ['lax', 'strict', 'none'])) $samesite = 'lax';


if (PHP_VERSION >= '5.2.0') {
# session_set_cookie_params(0, $path, (zen_not_null($cookieDomain) ? $domainPrefix . $cookieDomain : ''), $secureFlag, TRUE);
session_set_cookie_params(0, $path .'; samesite='.$samesite, (zen_not_null($cookieDomain) ? $domainPrefix . $cookieDomain : ''), $secureFlag, TRUE);
} else {
# session_set_cookie_params(0, $path, (zen_not_null($cookieDomain) ? $domainPrefix . $cookieDomain : ''), $secureFlag);
session_set_cookie_params(0, $path .'; samesite='.$samesite, (zen_not_null($cookieDomain) ? $domainPrefix . $cookieDomain : ''), $secureFlag);
}


Unfortunately, that did not fix the problem and I am still getting several payments a day but no order.

Any idea what might be causing it?