The function of APERAK is:

• To inform the sender of a message that the message has been received by the addressee's application but has been rejected due to errors
• To inform the sender of a message that it has been correctly received by the addressee's application.

The receiving application does not to stop at the first error but analyses the entire message. It enables the sender to correct the message sooner and ensures that it is ultimately accepted. This time saving can benefit various players in the supply chain.