"error":"Missingthe ajax controller"

Google has notified us about this error: When clicking on [https://www.allclaveparts.com/index.php?main_page=controller, it opens a new web page that simply states: {"error":"Missingthe ajax controller"}

I have had both my hosting company and the person responsible for taking care of the site. Neither can figure out what is going on. We only noticed this when Google pointed out the error today

Does anybody have any idea what is going on and what can be done to fix it?

I am using version 1.5.6a

Thank you

Where did your site's template come from? Was it purchased or "home-grown"?

That 'controller' page is not a built-in Zen Cart page.

Where did they get this link? Is it in your sitemap?

Is there a folder called includes/modules/pages/controller? You could start by removing that if you aren't sure what it does. (Make a backup before doing this of course.)

This is part of Zucando's Real-Time plugin which you're obviously using on your site. You should probably contact Zucando and see if they can help you resolve this.

I believe you just need an if-else statement to see if the request is AJAX or not, and if not simply do a redirect to a 404.