SAP Message CA_TTE459 - Enter a valid country for product &2 in product tax classification.

Procedure
From CRM Invoice/Order
In the SAP menu, choose Master Data -> Products -> MaintainProducts.
Choose product &V2& .
In the sub-screen Taxes, maintain data as required.
Choose Save.
From the TTE Simulation Tool
In the input document:
Choose Product
Choose the relevant product.
Use F4 to choose a country defined for the product.
Choose Save.
To update Customizing settings, choose ImmediateCustomizing Refresh.