Reservations challenges in Microsoft Dynamics Business Central

I would like to share another topic that drew my attention recently as I wasn’t aware of the “problem”.

Here is the simple scenario:

• Create a Sales Order and a Sales Line for an Item
  
• Create a Purchase Order and a Purchase Line for an Item
  
• Try to (auto) reserve the Sales Order Line against Purchase Order Line
  

I know what every customer expects. The expectation is that the reservation should be a fairly simple scenario, and that the reservation between the purchase order and the sales order created on the same day should be a fairly simple scenario to do. And indeed it is – unless you have an incorrect value in a field in the Manufacturing Setup table. In this case, it is not possible to make such a reservation. Wait, what has manufacturing got to do with the reservation? This was the first question that came to my mind. If you happen to be using manufacturing in BC, you might be setting some preferences in the manufacturing setup. But if you don’t, you probably don’t care and don’t want anything to do with the manufacturing module. The field that annoys me at the moment is called “Default Safety Lead Time”. If you have a non-empty value in this field – you will not be able to make reservations between sales and purchase orders.

If we change this field value to empty, voila:

“Default Safety Lead Time” field serves as formula in order to calculate the Expected Receipt Date for the purchase line. If there is a value of ‘1D’ in the ‘Default Safety Lead Time’ field in the manufacturing setup, the ‘Expected Receipt Date’ for the purchase line will be set to tomorrow when a purchase line is created – therefore the sales line scheduled to be shipped today cannot be reserved against this purchase line.

It is unlikely that everyone encounters this problem, as the field in the manufacturing setup has no value for W1. But in localised versions, for example in Germany, this value is set to ‘1D’. This was, in my opinion, an hour too many for a developer to spend trying to figure out where this behaviour came from – and I still cannot answer the question of why this field is in the manufacturing setup but is a default for the purchase lines. At the very least, if you are wondering why the reservation cannot be made, please check the Manufacturing Setup.