WCF Service does not start automatically when messages are available through MSMQ

This article helps you resolve the problem that occurs when the Windows Communication Foundation (WCF) service does not automatically start because of pending messages in the Message Queuing (MSMQ) queue.

Original product version:   Internet Information Services 8.0, Internet Information Services 8.5
Original KB number:   2974327


An IIS application pool is hosting two distinct WCF services where one uses the net.msmq binding and the other uses msmq.formatname binding. When messages to the WCF service that use the net.msmq binding are pending in the MSMQ queue, the WCF service will not automatically start.


This is by design. WAS is designed so that when a single IIS application pool has multiple WCF services that use mixed msmq binding types, the msmq.formatname service takes precedence, and the flag to restart the net.msmq service is set to no. Therefore only the service that uses msmq.formatname will automatically start the w3wp process for that application pool when messages become available in the MSMQ queue.


The workaround is to use two separate application pools for your WCF services, separating the two different msmq bindings.