If the Item Numbered entered (or Vendor Item Number) does not exist in the Item Master (or Vendor Item Master), the user will be prompted to add it.
Navigation: Tools >> Setup >> Company >> Setup GP PowerPack
Mark the box next to TWK-POP: Prompt to Add Non-Inventory Items, then click DONE.
The feature will be enabled for the current user. Other users must restart their Dynamics GP client to enable this feature.
Using Prompt to Add Non-Inventory Items
When you enter an Item Number on a PO that does not exist in the Item Master, you will be prompted to ADD it, or CONTINUE with the non-inventory Item Number.