I tried it, followed the instructions, and get this message:
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Warning: include_once(../../../../wp-load.php): failed to open stream: No such file or directory in H:\root\home\myaccount\www\mysite\wp-content\plugins\nopCommerce-Integration\api\getdata.php on line 4
Warning: include_once(): Failed opening '../../../../wp-load.php' for inclusion (include_path='.;C:\php\pear') in H:\root\home\myaccount\www\mysite\wp-content\plugins\nopCommerce-Integration\api\getdata.php on line 4
Warning: count(): Parameter must be an array or an object that implements Countable in H:\root\home\myaccount\www\mysite\wp-content\plugins\nopCommerce-Integration\index.php on line 902
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I've installed all plugins and made all code changes, and went over the instructions twice.
nopCommerce version 3.90
(with recapcha enabled)(https/SSL)
Wordpress Version 4.9.4 (http)
Any idea what part isn't working?