In the results section " You already defined ", you will find elements that you have already defined in your current environment, and be able to use them again.

Reuse - already defined elements.

If you are creating a new item ( in gateway creation screen, in MessageDefinition creation screen, in transformation creation, screen, in channel creation screen, ...), reusing an existing element means duplicating it.

Reuse - element duplicated.

If you are in the Channel Detail screen, and it is the first time you use this element, the element will just be assigned to the channel.

Reuse - element set in channel.

If you are in the Channel Detail screen, and the selected element is already used in other channels, you will get the option of duplicating or sharing it.

Reuse - element set in channel.