Product not stored, no ID

[stargazer1682]

I am working on a Virtuemart 2.6.6 store, that is experiencing a problem where it cannot create new products.  This is upgraded site that had been migrated from Joomla 1.5 to Joomla 2.5; and everything seemed to be working fine, except it won't create new products.  When you click Save or Save and Close, it'll display "Product successfully saved", but above it, it displays the error "vmError: Product not stored, no id". 
My working theory is that it has to do with the fact that, upon opening the form to create a new product, at the top of the form it reads "Product Information id: 0" which I would assume, when attempting to save it, is not a valid ID number.  I also tried cloning a product, to see if creating a "new" product that way would do anything, but it failed with the same error that it had no ID.  I don't have another working version of Virtuemart 2.6.6 to reference if that's how it normally works, so I may be mistaken, but can anyone shed any light on why the new products won't store?