Changing Product Control Type after use on a Sales Order.

If you're getting the error "Cannot change control type" when trying to change the control type of a product, check out this article.

Changing the Control type on a Product that is referenced on an existing Sales Order may prompt you with message:

"Cannot change control type because the product is referenced by a sales order."

This message is returned because the related Product was entered on existing Sales Orders as the original control type it was created with. Changing these Product Control types while the Product exists on Sales Orders or previous transaction history can cause Inventory and Costing discrepancies that cannot be easily resolved by the user.

Instead, you can use this workaround:

1. Rename the current Product to be something like: Product_OLD.
2. Select the ‘Copy Product’ button. Give this new product the original ProductID name: Product.
3. Set the Product Control Type to be what you want it to be now.
4. Mark Product_OLD as inactive.

For more information on Inventory Control types, check out this KB.