"The protocol 'net.msmq' is not supported."

Randolpho St. John — Tue, 28 Dec 2010 05:05:49 GMT

OMG, a new lesson! Will wonders never cease?

So I ran into an interesting issue setting up a WCF service to consume an MSMQ queue. I won't bother you with the details of how to actually build a WCF/MSMQ service; there are plenty of tutorials on the subject. I want to share with you an interesting error that I ran into and the surprisingly simple fix. The error occurs when attempting to generate a Service Reference or even simply browsing to the WSDL of your WCF/MSMQ service in the form of a YSOD with the following error:

"The protocol 'net.msmq' is not supported."

After a lot of Googling on the subject turning up plenty of questions with the same error but no answers. So I went digging into some application level config files on a server that already had a WCF/MSMQ service successfully set up by the network admin, and the answer was amazingly simple:

If you are hosting an MSMQ/WCF service in IIS, you have to tell IIS to allow net.msmq protocol. It's in the advanced settings for the application or site in which you are hosting the service.

.... aaaand, that's it.