Ok I solved my problem and I wanted to share.

We are using zen cart 1.3.8. My customer had added products to her website and added the attributes and updated her stock levels. The problem happened because one of the attributes was a read only size chart. For some reason (anyone have any ideas?) the cart didn't recognize that the products had any stock available for the products that had the size chart as one of its attributes.

However, simply deleting the read only attribute didn't solve the problem. I had to delete the original variant and REDO each variant for each stock item to make it work finally. FRUSTRATING! But so far very happy with the result that this fab attribute works again.

EchoTasha