Recently we upgraded one of our CRM 2013 Online to CRM 2015 Online Update 1. The approach was installing the solution from our dev to new CRM 2015 environment.
After the update when trying to create a new product we were getting the following error message
“2 is not a valid state code on product with Id 0977da8e-3368-e511-80fc-3863bb359f30”
We raised the support ticket and the resolution was to add the following line of code to the customization.xml file. It seemed that few of the State Code and Status Code were gone missing for the product entity.
Adding them back resolved the issue.
Hope it helps..