Colleen Morrow shows how to handle poison messages and other errors in Service Broker:
This type of situation, a message that can never be processed successfully, is known as a poison message. The name kind of makes it sound like there’s a problem with the message itself. And there might be. Perhaps the message format is wrong for what the receiving code was expecting. But maybe the problem is with the receiving code itself. Regardless of what causes the poison message, it has to be dealt with.
SQL Server has a built-in mechanism for handling poison messages. If a transaction that receives a message rolls back 5 times, SQL Server will disable the queue. So that means that all processing that depends on that queue will cease. Nice, huh? Because of this, it behooves you to make sure you include proper error handling in your message processing code. And how exactly you handle errors will depend on several factors:
Handling errors safely is a huge part of asynchronous programming.