"Page not Found" message on Checkout page

On my checkout page, I get a "Page not Found" message at the bottom of the screen (where the shopping cart initially displays) whenever I enter data into the address, city, state, etc. fields. For some reason, it does not do it for the First and Last name fields, just the various address fields.

The continue button works and the payment forms thereafter work, but it is disconserting to see the error message show up every time the user fills in his address.

I tried deleting the lines of code referring to the cart_wrapper, but then I get an error on the whole page saying it can't find the wrapper.

The code for the Name fields is identical to the address fields, so I can't figure out why they trigger the error, but not the name fields.

This page was created using the Checkout Wizard, so it is not something I did.

What could be causing this?

Attached is a copy of the checkout page.

I'll need to troubleshoot directly, see the private message section.

See private reply

I tried to look into this, but I'm getting a missing cart error when I click submit. Are you working on the pages now?

Please get back to the point you were at and post back and I'll debug it. Right now it looks like there is a missing cart file that needs to be uploaded.

I have the same errors today on my checkout page. What was the solution to this issue?
When I click the same as shipping button or some of the various shipping labels the confirm cart page disappears and I get a page not found error where the page once was.

Please post the url of the page where you are having the trouble. I need to see it first before I know where to look in the files.

Thanks Ray, My products page is https://www.kicreativeplastics.net/products_results.php and if you follow the add to cart then click the checkout button you are taken to the checkout page that I have the issue on https://www.kicreativeplastics.net/checkout.php

Thanks

It looks like you may need to upload this page:

webassist/framework/ajax_wrapper.php

Thanks Ray, that worked. I wonder why it didn't load? I uploaded all webassist files including dependent files. I will have to look better in the future. Thanks for your help.