Unsolicited messages are usually those received as a result of an error condition such as an alert. If a message is not solicited, it is first routed to the PPO. If the PPO is not available, the message is redirected to the system console.
Percolated messages can also be received as unsolicited messages. For additional information, see Message rerouting and percolation.
A solicited message (not a WTOR) that is destined for a program operator application (POA) that is not active will be converted to an unsolicited message and delivered as an unsolicited message. For additional information, see Message rerouting and percolation. There are also cases in which messages that may be expected to be solicited are changed to unsolicited due to an error condition. For example, INOPs override command processing, so the inactivation messages following an INOP are unsolicited. If a VARY INACT is done for an NCP and a hard INOP is received while it is inactivating, the messages about inactivation processing before the INOP will be solicited, but the messages after the INOP will be unsolicited.