http://developers.de/blogs/damir_dobric/archive/2012/07/19/how-to-remove-service-bus-server-and-workflow-host.aspxThis post is related to BETA version of Service Bus Server and Workflow Host which is used in Share Point 2013. It should help you to uninstall previous version of Service Bus and Workflow. Use the following procedure to remove Workflow and Service BusenCommunityServer 2008 SP1 (Build: 30619.63)