Why can't I choose a subinventory on an internal transfer item?
In some cases, you are unable to select a subinventory.
To be able to select a subinventory value for an internal transfer line item, all of the following must be true:
- 
            Subinventory selection for the item is enabled 
- 
            The item has an on-hand item quantity recorded 
- 
            The item is enabled for reservation 
- 
            The item does not have any subinventory restrictions in the source organization, or the subinventory is tied to the item and source organization 
Items assigned to a subinventory are restricted to that subinventory. Unrestricted items can be issued and received to any subinventory. Restricted items can only be issued and received to the subinventories on the list.