Error:
The Messaging Engine failed to add a receive location “rlAtlasMyExchangeName-RabbitMQ” with URL
“rabbit@VM3-NWalters.hg.mysite.net/Queue=D.Data.MySite.MyExchangeName&RoutingKey=D.Data.MySite.MyExchangeName”
to the adapter “RabbitMQ”. Reason: “None of the specified endpoints were reachable”.

Solution:
This means that either you cannot connect to the server (or maybe the user doesn’t have access).
In my case, it was a stupid typo, I had hg instead of hq in the Host Name.