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Hi;

There’s a debugging guide in the FAQ : https://www.ads-software.com/plugins/ajax-campaign-monitor-forms/faq/

thank you Lee Willis.

i have resolved this issue by adding following code.

add below code before line number 234 in cm-ajax-shortcode.php
var myresponse = data.replace(/(\r\n|\n|\r)/gm,'');

like
var myresponse = data.replace(/(\r\n|\n|\r)/gm,''); if (myresponse == 'SUCCESS') {...}

And add same line in cm-ajax-widget.php before line 192

Hi;

If you’re getting whitespace before the response then that may cause issue in other areas too – you should look into resolving that – although glad you got your immediate issue sorted.