What could prevent NServiceBus from moving messages to the error queue if there are exceptions when processing?

I have an application using NServiceBus to process messages, and while debugging I'm finding t开发者_Python百科hat exceptions may be thrown, and the message is lost. I've checked both the main and error queues, and the message was only attempted once.

Are there any common pitfalls that could cause this to happen?

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This is a known issue on the trunk, make sure to use the latest 2.0 build