On my custom "Forward To A Friend" page I have been getting reports that sometimes there's a security code to be entered before submitting and sometimes there's no code. Sometimes the code is entered and submitted and it asks you to try again but the emails are still forwarded. Other times the code works flawlessly.
How come some people will see it and others won't? When was this added? I don't recall seeing it before.
The captcha field will show up once you've entered several email addresses and sent the form a few times in a row, which is why you don't see it all the time. It's to deter spambots. After you've submitted the form a couple of times, the captcha will appear, at which point you'll need to enter the numbers to successfully submit the form again.