Refusing to allow items to be placed in the cart

Hi,

I noticed this during testing and I have had customer emails about this.

If a customer places an order in the cart and then decides to delete that item, if they then decided they actually DO want that item, the system is telling them

Limit reached. You can't add the product:
The cart is empty

and it won't let them buy anything.

What is this??? Thank You

It means that either the product, or an option/variant of that product has not stock, or other restrictions (like start/end sale dates) that don't allow the user to add the product in the cart or limits configured via the "limit" button of the products listing of the backend which disallows adding that product.
I can't say more without more information on the product that generates the issue and your settings.