When creating a new record, you often need to select an option from a master list of items that you created earlier in Setup.
If the setup item you need is not already in the list, you may be able to add a new item on the fly using the New button at the bottom of the drop-down list.
See the instructions in the topic Setup on the Fly under EventPro Setup.
New on-the-fly button in a drop-down list
