Why is an inactive item displaying in MRP?

An inactive item will display in MRP-generated results if that inactive item has current demand.  The system will not let you convert the suggestion into an actual Job or PO (because the item is inactive), but it displays so that you know there is demand for the item.  MRP will *not* ignore inactive items.  The objective of the inactive setting is to prevent future demand (SOs and Jobs) from using that item.  However, it is important to catch any already existing demand and cover it via MRP to ensure you do not have unforseen shortages.