MSMQ routes and delivers messages based on a combination of queue priority and message priority. Messages are routed and delivered first by queue priority, and then by message priority.
Queue priority (called the base priority) for public queues can be set by any MSMQ-based application with write permissions for the queue. The priority can be set at any time. The queue priority can be set from -32768 to 32767. The default priority for public queues is 0. Private queues do not support queue priority.
MSMQ-based applications can send messages with a priority of 0 through 7, 7 being the highest priority.
For more information on changing the base priority of a queue from your MSMQ-based application, see the MSMQ SDK. For more information on using MSMQ Explorer to change the base priority of a queue, see MSMQ Explorer Help.