If when booking in an order with TNT, the shipment fails and the error Article weight must be entered is displayed, as below.
The error means that the product in the order (not the overall order) does not have a weight assigned to it when it has come into Shiptheory.
To solve this, you will need to make sure that your products have a weight from within your Sales Channel connected with Shiptheory.
If you have any questions about this, you can contact our support team who will able to assist.