Hi Aseel,
Usually, this occurs when RabbitMQ hasn't been properly installed. You can verify this by looking at the RabbitMQ service in your services and if the description is empty, that means it didn't install correctly and you will have to uninstall/reinstall Rabbit MQ
You can read the KB for this issue here: 
http://portal.blueprism.com/customer-support/support-center#/path/1601193862
In this case, you can remove the RabbitMQ service and re-install the software without re-installing Decipher components. To do this, follow the steps below:
- 
Open CMD as administrator and navigate to the sbin folder (e.g. : -C:\Program Files\RabbitMQ Server\rabbitmq_server-3.8.2\sbin)
 
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Remove RabbitMQ service by: rabbitmq-service.bat remove
 
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Reinstall it by: rabbitmq-service.bat install
 
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Start the service by: rabbitmq-service.bat start
 
I hope this gets your system going.
Thanks!
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Gabe Marquez
Sr. Technical Consultant, Professional Services
Blue Prism
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