WARNING: ALL THE RABBITMQ DATA WILL BE LOST WITH THIS OPERATION. Please backup your rabbitmq database before doing this (check the documentation about).
If you change the name of the machine where RabbitMQ server is installed, you will see that the service will no longer be startable, this because RabbitMQ relays on the machine name to create and connect to the node, even if it is local.
To fix this problem, you just have to reinstall the rabbitmq windows service, by using the proper command line utility rabbitmq-service.bat
********************* Service control usage ********************* rabbitmq-service help - Display this help rabbitmq-service install - Install the RabbitMQ service rabbitmq-service remove - Remove the RabbitMQ service The following actions can also be accomplished by using Windows Services Management Console (services.msc): rabbitmq-service start - Start the RabbitMQ service rabbitmq-service stop - Stop the RabbitMQ service rabbitmq-service disable - Disable the RabbitMQ service rabbitmq-service enable - Enable the RabbitMQ service
- First start a command prompt as administrator and go to the rabbitmq-server-x sbin folder
cd %programfiles(x86)%\RabbitMQ Server\rabbitmq_server-3.3.2\sbin
- Uninstall the service
rabbitmq-service.bat remove
- Install the service
rabbitmq-service.bat install
This should recreate the service and configure it to start the node with the correct name.
If this doesn’t work you can follow the instruction on how to completely reset a rabbitmq server installation.
.Net Diaries 
Fuck me. I had to wipe everything rabbitMQ. I knew removing all the components would reset it. I was even playing with the service but never thought of uninstalling and re-installing.
Luckily this was on a dev machine.
Good to know, thanks!