AsyncUIBalloon is a string that contains a well-formed XML document ([XML1.0] section 2.1). The root element of the document MUST be the asyncPrintUIRequest element (section A balloonUI element (section MUST be nested within the AsyncPrintUIRequest markup at the point where it is referenced in the XML schema.

AsyncUIBalloon SHOULD be used by a printer driver on a server to deliver to a client UI the details of an event or a change in device status. Print servers SHOULD also use AsyncUIBalloon to send details about printer configuration changes, when available, to a client UI.<1>