BAdI interface method &1 should 'Emulate empty method implementation'

What causes this issue?

The option 'Emulate empty method implementation' is not set for the
interface method.
You should choose this runtime behavior in case you cannot make sure
that an implementation for this method will always exist, otherwise
runtime errors could occur.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Choose 'Emulate empty method implementation'.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.