SharePoint 2013 Workflow: Microsoft.SharePoint.SPException: App Management Shared Service Proxy is not installed.

Today I came across the following error when I tried to activate a SharePoint designer workflow feature: SharePoint 2013 Workflow: Microsoft.SharePoint.SPException: App Management Shared Service Proxy is not installed. So … read the sharepoint-2013-workflow-microsoft-sharepoint-spexception-app-management-shared-service-proxy-is-not-installed post