How to: Block Shipment for Negative Inventory
You can block outbound shipment for an item when a transaction results in a negative inventory for that item.
To block shipment for negative inventory
In the Search box, enter Sales & Receivables Setup, and then choose the related link.
In the Sales & Receivables Setup window, on the General FastTab, select the Block ship. when neg. invent. check box.
When this check box is selected, the inventory for all items is calculated when you post a sales shipment. If the transaction leads to a negative quantity in inventory for an item, an error message appears.
Choose the OK button.