This is part of the NServiceBus Upgrade Guide from Version 6 to 7, which also includes the following individual upgrade guides for specific components:
- Migrating MSMQ subscription messages
- Azure Service Bus Transport (Legacy) Upgrade Version 7 to 8
- RabbitMQ Transport Upgrade Version 4 to 5
- SQL Server Transport Upgrade Version 3 to 4
NServiceBus/ is no longer retrieved from the configuration file. Setting the connection string for timeouts and subscription persisters should be done via code.