So I just tried this on my live site 155f php5.6 and got the same red "Please verify that you are not a robot."

I modified the class.google_recaptcha.php file to comment out Reviews and Create Account captchas, as I only want this on my contact form.

Tested it and got the red alert.

Then I removed the <?php echo recaptcha_get_html(false); ?> line from my contact form, tested again and still got the same alert, even though the captcha box was not on the page.

So I've removed all files for now.

Any ideas on how I can debug this? No errors are showing in the logs folder.

Thanks.