Service Broker - Enabling Service Broker requires exclusive database access
If your trying to enable service broker and it is just hanging then you must have other connections accessing your database.
The enabling of service broker requires a database update lock, this is only possible if there are no other connections in the database. This is because a connection to database will place a shared lock on the database top make sure no one drops it. However this shared lock will block the update lock required to enable service broker.
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