For existing installations the RabbitMQ Storage Area can be moved using the following procedure;
Stop the RabbitMQ Service
Move the existing RabbitMQ folder to the new location
Often Located under the user that installed RabbitMQ’s AppData\Roaming folder, eg: C:\Users\DigiAdmin\AppData\Roaming\RabbitMQ
Change the System Environment variable
RABBITMQ_BASE to point to the new location
Restart the Server