Problem to stop Auto Bot to registertration form
<p>Auto bot is registering dummy users to my website. Today, I have implemented Captcha with additions of two numbers and store the result in SESSION variable. Only human can understand it and proceed with registration process. But I'm really confused that same bot is parsing the SESSION variable and entering correct value of addition of two numbers and get registered in the website with dummy user.</p>

<p>Is there any other feasible method to stop this bot to register dummy users?</p>

<p>I'm using Zen cart.</p>
