Working with MSMQ can be hard. Windows does not provide a tool to generated or edit messages on the queue. There are plenty of tools that can do that for you. Especially I like Mqueue Viewer
Authors describe Mqueue as Fast and free MSMQ management tool, to manage your messages and queues and I totally agree with that statement.
Some screen below can give you some more understanding.
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I think it is worth keeping such tool in dev-toolbox. You can download it from http://www.mqueue.net/