MSMQ Message Viewer?

MSMQ QXplorer

Free. Open source.

https://sourceforge.net/projects/msmqqxplorer/

There are a few options - all I found are commercial (not terribly expensive, but not free, either):

• Mqueue Viewer (free)

• Mulholland Q Set

• QueueExplorer

If you are using Visual Studio - Open Server Explorer under Servers/[Server Name] there is Message Queues folder that gives you view as well.