When a customer is using EDI billing, the server is set to ping the EDI site on a regular basis. This can vary by customer. The default is set to ping every 24 hours but some customers are set to ping every hour, others 90 minutes, etc.
This error can occur for a variety of reasons and sometimes the additional information provided in the error message will completely explain the problem. For example, most state EDI billing sites require periodic changes to the user password and the message will inform the user that the user name and password are not valid.
Other situations could include a connection glitch at the time of the ping. This will often resolve itself and the notification will not repeat. If a notification continues to occur, the customer will likely contact Vertex for assistance and the error can be investigated at that time.