How do I debug Query Notifications on SQL Server?

I am trying to get query notifications to work, but my application is not receiving any notifications. How do I debug Query Notifications?

I am using the code availble here http://www.codeproject.com/KB/database/chatter.aspx. I c开发者_运维百科an see that the queues, the services and the stored procedures are being created on the server, but the OnChange event on my SqlDependency object is not being fired.

Can I somehow track the notifications?

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See The Mysterious Notification, the troubleshooting tips section.